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v1 Opcodes

Ops have a 'cost' of 1 unless otherwise specified.

err

  • Bytecode: 0x00
  • Stack: ... → exits
  • Fail immediately.

sha256

  • Bytecode: 0x01
  • Stack: ..., A: []byte → ..., [32]byte
  • SHA256 hash of value A, yields [32]byte
  • Cost: 7

keccak256

  • Bytecode: 0x02
  • Stack: ..., A: []byte → ..., [32]byte
  • Keccak256 hash of value A, yields [32]byte
  • Cost: 26

sha512_256

  • Bytecode: 0x03
  • Stack: ..., A: []byte → ..., [32]byte
  • SHA512_256 hash of value A, yields [32]byte
  • Cost: 9

ed25519verify

  • Bytecode: 0x04
  • Stack: ..., A: []byte, B: [64]byte, C: [32]byte → ..., bool
  • for (data A, signature B, pubkey C) verify the signature of ("ProgData" || program_hash || data) against the pubkey => {0 or 1}
  • Cost: 1900
  • Mode: Signature

The 32 byte public key is the last element on the stack, preceded by the 64 byte signature at the second-to-last element on the stack, preceded by the data which was signed at the third-to-last element on the stack.

+

  • Bytecode: 0x08
  • Stack: ..., A: uint64, B: uint64 → ..., uint64
  • A plus B. Fail on overflow.

Overflow is an error condition which halts execution and fails the transaction. Full precision is available from addw.

-

  • Bytecode: 0x09
  • Stack: ..., A: uint64, B: uint64 → ..., uint64
  • A minus B. Fail if B > A.

/

  • Bytecode: 0x0a
  • Stack: ..., A: uint64, B: uint64 → ..., uint64
  • A divided by B (truncated division). Fail if B == 0.

divmodw is available to divide the two-element values produced by mulw and addw.

*

  • Bytecode: 0x0b
  • Stack: ..., A: uint64, B: uint64 → ..., uint64
  • A times B. Fail on overflow.

Overflow is an error condition which halts execution and fails the transaction. Full precision is available from mulw.

<

  • Bytecode: 0x0c
  • Stack: ..., A: uint64, B: uint64 → ..., bool
  • A less than B => {0 or 1}

>

  • Bytecode: 0x0d
  • Stack: ..., A: uint64, B: uint64 → ..., bool
  • A greater than B => {0 or 1}

<=

  • Bytecode: 0x0e
  • Stack: ..., A: uint64, B: uint64 → ..., bool
  • A less than or equal to B => {0 or 1}

>=

  • Bytecode: 0x0f
  • Stack: ..., A: uint64, B: uint64 → ..., bool
  • A greater than or equal to B => {0 or 1}

&&

  • Bytecode: 0x10
  • Stack: ..., A: uint64, B: uint64 → ..., bool
  • A is not zero and B is not zero => {0 or 1}

||

  • Bytecode: 0x11
  • Stack: ..., A: uint64, B: uint64 → ..., bool
  • A is not zero or B is not zero => {0 or 1}

==

  • Bytecode: 0x12
  • Stack: ..., A, B → ..., bool
  • A is equal to B => {0 or 1}

!=

  • Bytecode: 0x13
  • Stack: ..., A, B → ..., bool
  • A is not equal to B => {0 or 1}

!

  • Bytecode: 0x14
  • Stack: ..., A: uint64 → ..., uint64
  • A == 0 yields 1; else 0

len

  • Bytecode: 0x15
  • Stack: ..., A: []byte → ..., uint64
  • yields length of byte value A

itob

  • Bytecode: 0x16
  • Stack: ..., A: uint64 → ..., [8]byte
  • converts uint64 A to big-endian byte array, always of length 8

btoi

  • Bytecode: 0x17
  • Stack: ..., A: []byte → ..., uint64
  • converts big-endian byte array A to uint64. Fails if len(A) > 8. Padded by leading 0s if len(A) < 8.

btoi fails if the input is longer than 8 bytes.

%

  • Bytecode: 0x18
  • Stack: ..., A: uint64, B: uint64 → ..., uint64
  • A modulo B. Fail if B == 0.

|

  • Bytecode: 0x19
  • Stack: ..., A: uint64, B: uint64 → ..., uint64
  • A bitwise-or B

&

  • Bytecode: 0x1a
  • Stack: ..., A: uint64, B: uint64 → ..., uint64
  • A bitwise-and B

^

  • Bytecode: 0x1b
  • Stack: ..., A: uint64, B: uint64 → ..., uint64
  • A bitwise-xor B

~

  • Bytecode: 0x1c
  • Stack: ..., A: uint64 → ..., uint64
  • bitwise invert value A

mulw

  • Bytecode: 0x1d
  • Stack: ..., A: uint64, B: uint64 → ..., X: uint64, Y: uint64
  • A times B as a 128-bit result in two uint64s. X is the high 64 bits, Y is the low

intcblock

  • Syntax: intcblock UINT ... where UINT ...: a block of int constant values
  • Bytecode: 0x20 {varuint count, [varuint ...]}
  • Stack: ... → ...
  • prepare block of uint64 constants for use by intc

intcblock loads following program bytes into an array of integer constants in the evaluator. These integer constants can be referred to by intc and intc_* which will push the value onto the stack. Subsequent calls to intcblock reset and replace the integer constants available to the script.

intc

  • Syntax: intc I where I: an index in the intcblock
  • Bytecode: 0x21 {uint8}
  • Stack: ... → ..., uint64
  • Ith constant from intcblock

intc_0

  • Bytecode: 0x22
  • Stack: ... → ..., uint64
  • constant 0 from intcblock

intc_1

  • Bytecode: 0x23
  • Stack: ... → ..., uint64
  • constant 1 from intcblock

intc_2

  • Bytecode: 0x24
  • Stack: ... → ..., uint64
  • constant 2 from intcblock

intc_3

  • Bytecode: 0x25
  • Stack: ... → ..., uint64
  • constant 3 from intcblock

bytecblock

  • Syntax: bytecblock BYTES ... where BYTES ...: a block of byte constant values
  • Bytecode: 0x26 {varuint count, [varuint length, bytes ...]}
  • Stack: ... → ...
  • prepare block of byte-array constants for use by bytec

bytecblock loads the following program bytes into an array of byte-array constants in the evaluator. These constants can be referred to by bytec and bytec_* which will push the value onto the stack. Subsequent calls to bytecblock reset and replace the bytes constants available to the script.

bytec

  • Syntax: bytec I where I: an index in the bytecblock
  • Bytecode: 0x27 {uint8}
  • Stack: ... → ..., []byte
  • Ith constant from bytecblock

bytec_0

  • Bytecode: 0x28
  • Stack: ... → ..., []byte
  • constant 0 from bytecblock

bytec_1

  • Bytecode: 0x29
  • Stack: ... → ..., []byte
  • constant 1 from bytecblock

bytec_2

  • Bytecode: 0x2a
  • Stack: ... → ..., []byte
  • constant 2 from bytecblock

bytec_3

  • Bytecode: 0x2b
  • Stack: ... → ..., []byte
  • constant 3 from bytecblock

arg

  • Syntax: arg N where N: an arg index
  • Bytecode: 0x2c {uint8}
  • Stack: ... → ..., []byte
  • Nth LogicSig argument
  • Mode: Signature

arg_0

  • Bytecode: 0x2d
  • Stack: ... → ..., []byte
  • LogicSig argument 0
  • Mode: Signature

arg_1

  • Bytecode: 0x2e
  • Stack: ... → ..., []byte
  • LogicSig argument 1
  • Mode: Signature

arg_2

  • Bytecode: 0x2f
  • Stack: ... → ..., []byte
  • LogicSig argument 2
  • Mode: Signature

arg_3

  • Bytecode: 0x30
  • Stack: ... → ..., []byte
  • LogicSig argument 3
  • Mode: Signature

txn

  • Syntax: txn F where F: txn
  • Bytecode: 0x31 {uint8}
  • Stack: ... → ..., any
  • field F of current transaction

txn

Fields (see transaction reference)

Index Name Type Notes
0 Sender address 32 byte address
1 Fee uint64 microalgos
2 FirstValid uint64 round number
4 LastValid uint64 round number
5 Note []byte Any data up to 1024 bytes
6 Lease [32]byte 32 byte lease value
7 Receiver address 32 byte address
8 Amount uint64 microalgos
9 CloseRemainderTo address 32 byte address
10 VotePK [32]byte 32 byte address
11 SelectionPK [32]byte 32 byte address
12 VoteFirst uint64 The first round that the participation key is valid.
13 VoteLast uint64 The last round that the participation key is valid.
14 VoteKeyDilution uint64 Dilution for the 2-level participation key
15 Type []byte Transaction type as bytes
16 TypeEnum uint64 Transaction type as integer
17 XferAsset uint64 Asset ID
18 AssetAmount uint64 value in Asset's units
19 AssetSender address 32 byte address. Source of assets if Sender is the Asset's Clawback address.
20 AssetReceiver address 32 byte address
21 AssetCloseTo address 32 byte address
22 GroupIndex uint64 Position of this transaction within an atomic transaction group. A stand-alone transaction is implicitly element 0 in a group of 1
23 TxID [32]byte The computed ID for this transaction. 32 bytes.

global

  • Syntax: global F where F: global
  • Bytecode: 0x32 {uint8}
  • Stack: ... → ..., any
  • global field F

global

Fields

Index Name Type Notes
0 MinTxnFee uint64 microalgos
1 MinBalance uint64 microalgos
2 MaxTxnLife uint64 rounds
3 ZeroAddress address 32 byte address of all zero bytes
4 GroupSize uint64 Number of transactions in this atomic transaction group. At least 1

gtxn

  • Syntax: gtxn T F where T: transaction group index, F: txn
  • Bytecode: 0x33 {uint8}, {uint8}
  • Stack: ... → ..., any
  • field F of the Tth transaction in the current group

for notes on transaction fields available, see txn. If this transaction is i in the group, gtxn i field is equivalent to txn field.

load

  • Syntax: load I where I: position in scratch space to load from
  • Bytecode: 0x34 {uint8}
  • Stack: ... → ..., any
  • Ith scratch space value. All scratch spaces are 0 at program start.

store

  • Syntax: store I where I: position in scratch space to store to
  • Bytecode: 0x35 {uint8}
  • Stack: ..., A → ...
  • store A to the Ith scratch space

bnz

  • Syntax: bnz TARGET where TARGET: branch offset
  • Bytecode: 0x40 {int16 (big-endian)}
  • Stack: ..., A: uint64 → ...
  • branch to TARGET if value A is not zero

The bnz instruction opcode 0x40 is followed by two immediate data bytes which are a high byte first and low byte second which together form a 16 bit offset which the instruction may branch to. For a bnz instruction at pc, if the last element of the stack is not zero then branch to instruction at pc + 3 + N, else proceed to next instruction at pc + 3. Branch targets must be aligned instructions. (e.g. Branching to the second byte of a 2 byte op will be rejected.) Starting at v4, the offset is treated as a signed 16 bit integer allowing for backward branches and looping. In prior version (v1 to v3), branch offsets are limited to forward branches only, 0-0x7fff.

At v2 it became allowed to branch to the end of the program exactly after the last instruction: bnz to byte N (with 0-indexing) was illegal for a TEAL program with N bytes before v2, and is legal after it. This change eliminates the need for a last instruction of no-op as a branch target at the end. (Branching beyond the end--in other words, to a byte larger than N--is still illegal and will cause the program to fail.)

pop

  • Bytecode: 0x48
  • Stack: ..., A → ...
  • discard A

dup

  • Bytecode: 0x49
  • Stack: ..., A → ..., A, A
  • duplicate A