> ## Documentation Index
> Fetch the complete documentation index at: https://voltaire.tevm.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# name()

> Get EVM opcode mnemonic name

<Card title="Try it Live" icon="play" href="https://playground.tevm.sh?example=primitives/opcode.ts">
  Run Opcode examples in the interactive playground
</Card>

## Opcode.name()

Get opcode mnemonic name.

<Tabs>
  <Tab title="Functional API">
    ```typescript theme={null}
    import { name, ADD, PUSH1, SLOAD } from 'tevm/Opcode'

    name(0x01)   // "ADD"
    name(PUSH1)  // "PUSH1"
    name(SLOAD)  // "SLOAD"
    ```
  </Tab>
</Tabs>

## Parameters

* `opcode: BrandedOpcode` - Opcode byte (0x00-0xFF)

## Returns

`string | undefined` - Mnemonic name or undefined if invalid

## All Opcode Names

### Arithmetic (0x00-0x0B)

```typescript theme={null}
Opcode.name(0x00)  // "STOP"
Opcode.name(0x01)  // "ADD"
Opcode.name(0x02)  // "MUL"
Opcode.name(0x03)  // "SUB"
Opcode.name(0x04)  // "DIV"
Opcode.name(0x05)  // "SDIV"
Opcode.name(0x06)  // "MOD"
Opcode.name(0x07)  // "SMOD"
Opcode.name(0x08)  // "ADDMOD"
Opcode.name(0x09)  // "MULMOD"
Opcode.name(0x0A)  // "EXP"
Opcode.name(0x0B)  // "SIGNEXTEND"
```

### Comparison (0x10-0x14)

```typescript theme={null}
Opcode.name(0x10)  // "LT"
Opcode.name(0x11)  // "GT"
Opcode.name(0x12)  // "SLT"
Opcode.name(0x13)  // "SGT"
Opcode.name(0x14)  // "EQ"
```

### Bitwise (0x15-0x1D)

```typescript theme={null}
Opcode.name(0x15)  // "ISZERO"
Opcode.name(0x16)  // "AND"
Opcode.name(0x17)  // "OR"
Opcode.name(0x18)  // "XOR"
Opcode.name(0x19)  // "NOT"
Opcode.name(0x1A)  // "BYTE"
Opcode.name(0x1B)  // "SHL"
Opcode.name(0x1C)  // "SHR"
Opcode.name(0x1D)  // "SAR"
```

### Cryptographic (0x20)

```typescript theme={null}
Opcode.name(0x20)  // "KECCAK256"
```

### Environmental (0x30-0x3F)

```typescript theme={null}
Opcode.name(0x30)  // "ADDRESS"
Opcode.name(0x31)  // "BALANCE"
Opcode.name(0x32)  // "ORIGIN"
Opcode.name(0x33)  // "CALLER"
Opcode.name(0x34)  // "CALLVALUE"
Opcode.name(0x35)  // "CALLDATALOAD"
Opcode.name(0x36)  // "CALLDATASIZE"
Opcode.name(0x37)  // "CALLDATACOPY"
Opcode.name(0x38)  // "CODESIZE"
Opcode.name(0x39)  // "CODECOPY"
Opcode.name(0x3A)  // "GASPRICE"
Opcode.name(0x3B)  // "EXTCODESIZE"
Opcode.name(0x3C)  // "EXTCODECOPY"
Opcode.name(0x3D)  // "RETURNDATASIZE"
Opcode.name(0x3E)  // "RETURNDATACOPY"
Opcode.name(0x3F)  // "EXTCODEHASH"
```

### Stack/Memory/Storage (0x50-0x5F)

```typescript theme={null}
Opcode.name(0x50)  // "POP"
Opcode.name(0x51)  // "MLOAD"
Opcode.name(0x52)  // "MSTORE"
Opcode.name(0x53)  // "MSTORE8"
Opcode.name(0x54)  // "SLOAD"
Opcode.name(0x55)  // "SSTORE"
Opcode.name(0x56)  // "JUMP"
Opcode.name(0x57)  // "JUMPI"
Opcode.name(0x58)  // "PC"
Opcode.name(0x59)  // "MSIZE"
Opcode.name(0x5A)  // "GAS"
Opcode.name(0x5B)  // "JUMPDEST"
Opcode.name(0x5F)  // "PUSH0"
```

### PUSH (0x60-0x7F)

```typescript theme={null}
Opcode.name(0x60)  // "PUSH1"
Opcode.name(0x61)  // "PUSH2"
// ... PUSH3-PUSH31
Opcode.name(0x7F)  // "PUSH32"
```

### DUP (0x80-0x8F)

```typescript theme={null}
Opcode.name(0x80)  // "DUP1"
Opcode.name(0x81)  // "DUP2"
// ... DUP3-DUP15
Opcode.name(0x8F)  // "DUP16"
```

### SWAP (0x90-0x9F)

```typescript theme={null}
Opcode.name(0x90)  // "SWAP1"
Opcode.name(0x91)  // "SWAP2"
// ... SWAP3-SWAP15
Opcode.name(0x9F)  // "SWAP16"
```

### LOG (0xA0-0xA4)

```typescript theme={null}
Opcode.name(0xA0)  // "LOG0"
Opcode.name(0xA1)  // "LOG1"
Opcode.name(0xA2)  // "LOG2"
Opcode.name(0xA3)  // "LOG3"
Opcode.name(0xA4)  // "LOG4"
```

### System (0xF0-0xFF)

```typescript theme={null}
Opcode.name(0xF0)  // "CREATE"
Opcode.name(0xF1)  // "CALL"
Opcode.name(0xF2)  // "CALLCODE"
Opcode.name(0xF3)  // "RETURN"
Opcode.name(0xF4)  // "DELEGATECALL"
Opcode.name(0xF5)  // "CREATE2"
Opcode.name(0xFA)  // "STATICCALL"
Opcode.name(0xFD)  // "REVERT"
Opcode.name(0xFE)  // "INVALID"
Opcode.name(0xFF)  // "SELFDESTRUCT"
```

## Use Cases

### Disassembly

```typescript theme={null}
function simpleDisassemble(bytecode: Uint8Array): string[] {
  const instructions = Opcode.parse(bytecode)
  return instructions.map(inst => {
    const name = Opcode.name(inst.opcode) ?? `UNKNOWN_${inst.opcode.toString(16)}`
    return `${inst.offset}: ${name}`
  })
}
```

### Filter by Name

```typescript theme={null}
function findOpcodesByName(
  bytecode: Uint8Array,
  targetName: string
): number[] {
  const instructions = Opcode.parse(bytecode)
  const offsets: number[] = []

  for (const inst of instructions) {
    if (Opcode.name(inst.opcode) === targetName) {
      offsets.push(inst.offset)
    }
  }

  return offsets
}

// Find all SSTORE operations
const sstoreLocations = findOpcodesByName(bytecode, 'SSTORE')
```

### Count Opcode Usage

```typescript theme={null}
function countOpcodeUsage(bytecode: Uint8Array): Map<string, number> {
  const instructions = Opcode.parse(bytecode)
  const counts = new Map<string, number>()

  for (const inst of instructions) {
    const name = Opcode.name(inst.opcode)
    if (name) {
      counts.set(name, (counts.get(name) ?? 0) + 1)
    }
  }

  return counts
}
```

### Reverse Lookup

```typescript theme={null}
function findOpcodeByName(name: string): number | undefined {
  for (let i = 0; i <= 0xFF; i++) {
    if (Opcode.name(i) === name) {
      return i
    }
  }
  return undefined
}

const pushOpcode = findOpcodeByName('PUSH1')  // 0x60
```

## Performance

* **O(1)** lookup time
* **Pre-computed** string table
* **Zero allocation** for query
* Very fast

## Related

* [info()](/primitives/opcode/info) - Get full metadata
* [isValid()](/primitives/opcode/is-valid) - Check if opcode exists
* [format()](/primitives/opcode/format) - Format instruction with name
* [disassemble()](/primitives/opcode/disassemble) - Disassemble with names