Opcodes · arithmetic · enabled

OP_LSHIFTNUM (0x8d)

Arithmetic left shift: multiplies number a by 2 to the power `bits`. Negative shift counts fail. This byte was the disabled OP_2MUL before May 2026.

Verified
Stack in → out
a bits → a×2^bits
Since
May 2026 (Layla): loops, functions, bitwise ops and Pay-to-Script
Cost
Base instruction cost 100 plus the byte length of the pushed result (2025 VM limits). Fails if the result exceeds 10,000 bytes.
Bitcoin status
Disabled in Bitcoin (BTC)0x8d is the disabled OP_2MUL in BTC; an OP_SUCCESS code in Tapscript.

Example

OP_3 OP_2 OP_LSHIFTNUM OP_12 OP_EQUAL

Step through it opcode by opcode in Bitauth IDE, the in-browser BCH VM debugger.

Sources

  1. CHIP-2025-05 Bitwise: Re-Enable Bitwise Operations
  2. Libauth BCH_2026_05 opcodes (bch-2026-opcodes.ts)
  3. Announcing Bitcoin Cash Node v29.0.0