This page provides a description of all instructions for the FuelVM. Encoding is read as a sequence of one 8-bit value (the opcode identifier) followed by four 6-bit values (the register identifiers or immediate value). A single i indicates a 6-bit immediate value, i i indicates a 12-bit immediate value, i i i indicates an 18-bit immediate value, and i i i i indicates a 24-bit immediate value. All immediate values are interpreted as big-endian unsigned integers.
The syntax MEM[x, y] used in this page means the memory range starting at byte x, of length y bytes. The syntax STATE[x, y] used in this page means the sequence of storage slots starting at key x and spanning y bytes. Some instructions may
panic , i.e. enter an unrecoverable state. Additionally, attempting to execute an instruction not in this list causes a panic and consumes no gas. How a panic is handled depends on
context :
In a predicate context, cease VM execution and return false. In other contexts, revert (described below). On a non-predicate panic, append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.Panicidbyte[32]Contract ID of current context if in an internal context, zero otherwise. pcuint64Value of register $pc. isuint64Value of register $is.
then append an additional receipt to the list of receipts, again modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.ScriptResultresultuint641gas_useduint64Gas consumed by the script.
The number of receipts is limited to 216, with the last two reserved to panic and script result receipts. Trying to add any other receipts after 216-2 will panic.
A few instructions are annotated with the effects they produce, the table below explains each effect:
effect name description Storage read Instruction reads from storage slots Storage write Instruction writes to storage slots External call External contract call instruction Balance tree read Instruction reads from the balance tree Balance tree write Instruction writes to the balance tree Output message Instruction sends a message to a recipient address
If an instruction is not annotated with an effect, it means it does not produce any of the aforementioned affects.
All these instructions advance the program counter $pc by 4 after performing their operation.
Normally, if the result of an ALU operation is mathematically undefined (e.g. dividing by zero),
the VM panics. However, if the
F_UNSAFEMATH flag is set,
$err is set to
true
and execution continues.
If an operation would overflow, so that the result doesn't fit into the target field, the VM will panic.
Results below zero are also considered overflows. If the
F_WRAPPING flag is set,
instead
$of is set to
true or the overflowing part of the result, depending on the operation.
Description Adds two registers. Operation $rA = $rB + $rC;Syntax add $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$of is assigned the overflow of the operation.
$err is cleared.
Description Adds a register and an immediate value. Operation $rA = $rB + imm;Syntax addi $rA, $rB, immediateEncoding 0x00 rA rB i iNotes
Panic if:
$of is assigned the overflow of the operation.
$err is cleared.
Description Bitwise ANDs two registers. Operation $rA = $rB & $rC;Syntax and $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$of and $err are cleared.
Description Bitwise ANDs a register and an immediate value. Operation $rA = $rB & imm;Syntax andi $rA, $rB, immEncoding 0x00 rA rB i iNotes
Panic if:
imm is extended to 64 bits, with the high 52 bits set to 0.
$of and $err are cleared.
Description Divides two registers. Operation $rA = $rB // $rC;Syntax div $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
If $rC == 0, $rA is cleared and $err is set to true.
Otherwise, $err is cleared.
$of is cleared.
Description Divides a register and an immediate value. Operation $rA = $rB // imm;Syntax divi $rA, $rB, immEncoding 0x00 rA rB i iNotes
Panic if:
If imm == 0, $rA is cleared and $err is set to true.
Otherwise, $err is cleared.
$of is cleared.
Description Compares two registers for equality. Operation $rA = $rB == $rC;Syntax eq $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$of and $err are cleared.
Description Raises one register to the power of another. Operation $rA = $rB ** $rC;Syntax exp $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
If the result cannot fit in 8 bytes, $of is set to 1 and $rA is instead set to 0, otherwise $of is cleared.
$err is cleared.
Description Raises one register to the power of an immediate value. Operation $rA = $rB ** imm;Syntax expi $rA, $rB, immEncoding 0x00 rA rB i iNotes
Panic if:
If the result cannot fit in 8 bytes, $of is set to 1 and $rA is instead set to 0, otherwise $of is cleared.
$err is cleared.
Description Compares two registers for greater-than. Operation $rA = $rB > $rC;Syntax gt $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$of and $err are cleared.
Description Compares two registers for less-than. Operation $rA = $rB < $rC;Syntax lt $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$of and $err are cleared.
Description The (integer) logarithm base $rC of $rB. Operation $rA = math.floor(math.log($rB, $rC));Syntax mlog $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
If $rB == 0, both $rA and $of are cleared and $err is set to true.
If $rC <= 1, both $rA and $of are cleared and $err is set to true.
Otherwise, $of and $err are cleared.
Description Modulo remainder of two registers. Operation $rA = $rB % $rC;Syntax mod $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
If $rC == 0, both $rA and $of are cleared and $err is set to true.
Otherwise, $of and $err are cleared.
Description Modulo remainder of a register and an immediate value. Operation $rA = $rB % imm;Syntax modi $rA, $rB, immEncoding 0x00 rA rB i iNotes
Panic if:
If imm == 0, both $rA and $of are cleared and $err is set to true.
Otherwise, $of and $err are cleared.
Description Copy from one register to another. Operation $rA = $rB;Syntax move $rA, $rBEncoding 0x00 rA rB - -Notes
Panic if:
$of and $err are cleared.
Description Copy an immediate value into a register. Operation $rA = imm;Syntax movi $rA, immEncoding 0x00 rA i i iNotes
Panic if:
$of and $err are cleared.
Description The (integer) $rCth root of $rB. Operation $rA = math.floor(math.root($rB, $rC));Syntax mroo $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
If $rC == 0, both $rA and $of are cleared and $err is set to true.
Otherwise, $of and $err are cleared.
Description Multiplies two registers. Operation $rA = $rB * $rC;Syntax mul $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$of is assigned the overflow of the operation.
$err is cleared.
Description Multiplies a register and an immediate value. Operation $rA = $rB * imm;Syntax mul $rA, $rB, immEncoding 0x00 rA rB i iNotes
Panic if:
$of is assigned the overflow of the operation.
$err is cleared.
Description Multiplies two registers with arbitrary precision, then divides by a third register. Operation a = (b * c) / d;Syntax mldv $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDNotes Division by zero is treated as division by 1 << 64 instead.
If the divisor ($rD) is zero, then instead the value is divided by 1 << 64. This returns the higher half of the 128-bit multiplication result. This operation never overflows.
If the result of after the division doesn't fit into a register, $of is assigned the overflow of the operation. Otherwise, $of is cleared.
$err is cleared.
Description Performs no operation. Operation Syntax noopEncoding 0x00 - - - -Notes
$of and $err are cleared.
Description Bitwise NOT a register. Operation $rA = ~$rB;Syntax not $rA, $rBEncoding 0x00 rA rB - -Notes
Panic if:
$of and $err are cleared.
Description Bitwise ORs two registers. Operation $rA = $rB | $rC;Syntax or $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$of and $err are cleared.
Description Bitwise ORs a register and an immediate value. Operation $rA = $rB | imm;Syntax ori $rA, $rB, immEncoding 0x00 rA rB i iNotes
Panic if:
imm is extended to 64 bits, with the high 52 bits set to 0.
$of and $err are cleared.
Description Left shifts a register by a register. Operation $rA = $rB << $rC;Syntax sll $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes Zeroes are shifted in.
Panic if:
$of and $err are cleared.
Description Left shifts a register by an immediate value. Operation $rA = $rB << imm;Syntax slli $rA, $rB, immEncoding 0x00 rA rB i iNotes Zeroes are shifted in.
Panic if:
$of and $err are cleared.
Description Right shifts a register by a register. Operation $rA = $rB >> $rC;Syntax srl $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes Zeroes are shifted in.
Panic if:
$of and $err are cleared.
Description Right shifts a register by an immediate value. Operation $rA = $rB >> imm;Syntax srli $rA, $rB, immEncoding 0x00 rA rB i iNotes Zeroes are shifted in.
Panic if:
$of and $err are cleared.
Description Subtracts two registers. Operation $rA = $rB - $rC;Syntax sub $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes $of is assigned the overflow of the operation.
Panic if:
$of is assigned the underflow of the operation, as though $of is the high byte of a 128-bit register.
$err is cleared.
Description Subtracts a register and an immediate value. Operation $rA = $rB - imm;Syntax subi $rA, $rB, immEncoding 0x00 rA rB i iNotes $of is assigned the overflow of the operation.
Panic if:
$of is assigned the underflow of the operation, as though $of is the high byte of a 128-bit register.
$err is cleared.
Description Compare or examine two 128-bit integers using selected mode Operation b = mem[$rB,16];c = indirect?mem[$rC,16]:$rC;$rA = cmp_op(b,c);Syntax wdcm $rA, $rB, $rC, immEncoding 0x00 rA rB rC iNotes
The six-bit immediate value is used to select operating mode, as follows:
Bits Short name Description ...XXXmodeCompare mode selection .XX...reservedReserved and must be zero X.....indirectIs rhs operand ($rC) indirect or not
Then the actual operation that's performed:
modeName Description 0 eqEquality (==) 1 neInequality (!=) 2 ltLess than (<) 3 gtGreater than (>) 4 lteLess than or equals (<=) 5 gteGreater than or equals (>=) 6 lzcLeading zero count the lhs argument (lzcnt). Discards rhs. 7 - Reserved and must not be used
The leading zero count can be used to compute rounded-down log2 of a number using the following formula TOTAL_BITS - 1 - lzc(n). Note that log2(0) is undefined, and will lead to integer overflow with this method.
Clears $of and $err.
Panic if:
A reserved compare mode is given $rA is a reserved register $rB + 16 overflows or > VM_MAX_RAM indirect == 1 and $rC + 16 overflows or > VM_MAX_RAM Description Compare or examine two 256-bit integers using selected mode Operation b = mem[$rB,32];c = indirect?mem[$rC,32]:$rC;$rA = cmp_op(b,c);Syntax wqcm $rA, $rB, $rC, immEncoding 0x00 rA rB rC iNotes
The immediate value is interpreted identically to WDCM.
Clears $of and $err.
Panic if:
A reserved compare mode is given $rA is a reserved register $rB + 32 overflows or > VM_MAX_RAM indirect == 1 and $rC + 32 overflows or > VM_MAX_RAM Description Perform an ALU operation on two 128-bit integers Operation b = mem[$rB,16];c = indirect?mem[$rC,16]:$rC;mem[$rA,16] = op(b,c);Syntax wdop $rA, $rB, $rC, immEncoding 0x00 rA rB rC iNotes
The six-bit immediate value is used to select operating mode, as follows:
Bits Short name Description ...XXXopOperation selection, see below .XX...reservedReserved and must be zero X.....indirectIs rhs operand ($rC) indirect or not
Then the actual operation that's performed:
opName Description 0 addAdd 1 subSubtract 2 notInvert bits (discards rhs) 3 orBitwise or 4 xorBitwise exclusive or 5 andBitwise and 6 shlShift left (logical) 7 shrShift right (logical)
Operations behave $of and $err similarly to their 64-bit counterparts, except that $of is set to 1 instead of the overflowing part.
Panic if:
Reserved bits of the immediate are set The memory range MEM[$rA, 16] does not pass ownership check $rB + 16 overflows or > VM_MAX_RAM indirect == 1 and $rC + 16 overflows or > VM_MAX_RAM Description Perform an ALU operation on two 256-bit integers Operation b = mem[$rB,32];c = indirect?mem[$rC,32]:$rC;mem[$rA,32] = op(b,c);Syntax wqop $rA, $rB, $rC, immEncoding 0x00 rA rB rC iNotes
The immediate value is interpreted identically to WDOP.
Operations behave $of and $err similarly to their 64-bit counterparts.
Panic if:
Reserved bits of the immediate are set The memory range MEM[$rA, 32] does not pass ownership check $rB + 32 overflows or > VM_MAX_RAM indirect == 1 and $rC + 32 overflows or > VM_MAX_RAM Description Perform integer multiplication operation on two 128-bit integers. Operation b=indirect0?mem[$rB,16]:$rB;c=indirect1?mem[$rC,16]:$rC;mem[$rA,16]=b*c;Syntax wdml $rA, $rB, $rC, immEncoding 0x00 rA rB rC iNotes
The six-bit immediate value is used to select operating mode, as follows:
Bits Short name Description ..XXXXreservedReserved and must be zero .X....indirect0Is lhs operand ($rB) indirect or not X.....indirect1Is rhs operand ($rC) indirect or not
$of is set to 1 in case of overflow, and cleared otherwise.
$err is cleared.
Panic if:
Reserved bits of the immediate are set The memory range MEM[$rA, 16] does not pass ownership check indirect0 == 1 and $rB + 16 overflows or > VM_MAX_RAM indirect1 == 1 and $rC + 16 overflows or > VM_MAX_RAM Description Perform integer multiplication operation on two 256-bit integers. Operation b=indirect0?mem[$rB,32]:$rB;c=indirect1?mem[$rC,32]:$rC;mem[$rA,32]=b*c;Syntax wqml $rA, $rB, $rC, immEncoding 0x00 rA rB rC iNotes
The immediate value is interpreted identically to WDML.
$of is set to 1 in case of overflow, and cleared otherwise.
$err is cleared.
Panic if:
Reserved bits of the immediate are set The memory range MEM[$rA, 32] does not pass ownership check indirect0 == 1 and $rB + 32 overflows or > VM_MAX_RAM indirect1 == 1 and $rC + 32 overflows or > VM_MAX_RAM Description Divide a 128-bit integer by another. Operation b = mem[$rB,16];c = indirect?mem[$rC,16]:$rC;mem[$rA,16] = b / c;Syntax wddv $rA, $rB, $rC, immEncoding 0x00 rA rB rC iNotes
The six-bit immediate value is used to select operating mode, as follows:
Bits Short name Description .XXXXXreservedReserved and must be zero X.....indirectIs rhs operand ($rC) indirect or not
$of is cleared.
If the rhs operand is zero, MEM[$rA, 16] is cleared and $err is set to true. Otherwise, $err is cleared.
Panic if:
Reserved bits of the immediate are set The memory range MEM[$rA, 16] does not pass ownership check $rB + 16 overflows or > VM_MAX_RAM indirect == 1 and $rC + 16 overflows or > VM_MAX_RAM Description Divide a 256-bit integer by another. Operation b = mem[$rB,32];c = indirect?mem[$rC,32]:$rC;mem[$rA,32] = b / c;Syntax wqdv $rA, $rB, $rC, immEncoding 0x00 rA rB rC iNotes
The immediate value is interpreted identically to WDDV.
$of is cleared.
If the rhs operand is zero, MEM[$rA, 32] is cleared and $err is set to true. Otherwise, $err is cleared.
Panic if:
Reserved bits of the immediate are set The memory range MEM[$rA, 32] does not pass ownership check $rB + 32 overflows or > VM_MAX_RAM indirect == 1 and $rC + 32 overflows or > VM_MAX_RAM Description Combined multiply-divide of 128-bit integers with arbitrary precision. Operation b=mem[$rB,16];c=mem[$rC,16];d=mem[$rD,16];mem[$rA,16]=(b * c) / d;Syntax wddv $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDNotes Division by zero is treated as division by 1 << 128 instead.
If the divisor MEM[$rA, 16] is zero, then instead the value is divided by 1 << 128. This returns the higher half of the 256-bit multiplication result.
If the result of after the division is larger than operand size, $of is set to one. Otherwise, $of is cleared.
$err is cleared.
Panic if:
The memory range MEM[$rA, 16] does not pass ownership check $rB + 16 overflows or > VM_MAX_RAM $rC + 16 overflows or > VM_MAX_RAM $rD + 16 overflows or > VM_MAX_RAM Description Combined multiply-divide of 256-bit integers with arbitrary precision. Operation b=mem[$rB,32];c=mem[$rC,32];d=mem[$rD,32];mem[$rA,32]=(b * c) / d;Syntax wqdv $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDNotes Division by zero is treated as division by 1 << 256 instead.
If the divisor MEM[$rA, 32] is zero, then instead the value is divided by 1 << 256. This returns the higher half of the 512-bit multiplication result.
If the result of after the division is larger than operand size, $of is set to one. Otherwise, $of is cleared.
$err is cleared.
Panic if:
The memory range MEM[$rA, 32] does not pass ownership check $rB + 32 overflows or > VM_MAX_RAM $rC + 32 overflows or > VM_MAX_RAM $rD + 32 overflows or > VM_MAX_RAM Description Add two 128-bit integers and compute modulo remainder with arbitrary precision. Operation b=mem[$rB,16];c=mem[$rC,16];d=mem[$rD,16];mem[$rA,16] = (b+c)%d;Syntax wdam $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDNotes
$of is cleared.
If the rhs operand is zero, MEM[$rA, 16] is cleared and $err is set to true. Otherwise, $err is cleared.
Panic if:
The memory range MEM[$rA, 16] does not pass ownership check $rB + 16 overflows or > VM_MAX_RAM $rC + 16 overflows or > VM_MAX_RAM $rD + 16 overflows or > VM_MAX_RAM Description Add two 256-bit integers and compute modulo remainder with arbitrary precision. Operation b=mem[$rB,32];c=mem[$rC,32];d=mem[$rD,32];mem[$rA,32] = (b+c)%d;Syntax wdam $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDNotes
$of is cleared.
If the rhs operand is zero, MEM[$rA, 16] is cleared and $err is set to true. Otherwise, $err is cleared.
Panic if:
The memory range MEM[$rA, 32] does not pass ownership check $rB + 32 overflows or > VM_MAX_RAM $rC + 32 overflows or > VM_MAX_RAM $rD + 32 overflows or > VM_MAX_RAM Description Multiply two 128-bit integers and compute modulo remainder with arbitrary precision. Operation b=mem[$rB,16];c=mem[$rC,16];d=mem[$rD,16];mem[$rA,16] = (b*c)%d;Syntax wdmm $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDNotes
$of is cleared.
If the rhs operand is zero, MEM[$rA, 16] is cleared and $err is set to true. Otherwise, $err is cleared.
Panic if:
The memory range MEM[$rA, 16] does not pass ownership check $rB + 16 overflows or > VM_MAX_RAM $rC + 16 overflows or > VM_MAX_RAM $rD + 16 overflows or > VM_MAX_RAM Description Multiply two 256-bit integers and compute modulo remainder with arbitrary precision. Operation b=mem[$rB,32];c=mem[$rC,32];d=mem[$rD,32];mem[$rA,32] = (b*c)%d;Syntax wqmm $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDNotes
$of is cleared.
If the rhs operand is zero, MEM[$rA, 16] is cleared and $err is set to true. Otherwise, $err is cleared.
Panic if:
The memory range MEM[$rA, 32] does not pass ownership check $rB + 32 overflows or > VM_MAX_RAM $rC + 32 overflows or > VM_MAX_RAM $rD + 32 overflows or > VM_MAX_RAM Description Bitwise XORs two registers. Operation $rA = $rB ^ $rC;Syntax xor $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$of and $err are cleared.
Description Bitwise XORs a register and an immediate value. Operation $rA = $rB ^ imm;Syntax xori $rA, $rB, immEncoding 0x00 rA rB i iNotes
Panic if:
$of and $err are cleared.
Description Jumps to the code instruction offset by a register. Operation $pc = $is + $rA * 4;Syntax jmp $rAEncoding 0x00 rA - - -Notes
Panic if:
$is + $rA * 4 > VM_MAX_RAM - 1 Description Jumps to the code instruction offset by imm. Operation $pc = $is + imm * 4;Syntax ji immEncoding 0x00 i i i iNotes
Panic if:
$is + imm * 4 > VM_MAX_RAM - 1 Description Jump to the code instruction offset by a register if $rA is not equal to $rB. Operation if $rA != $rB:$pc = $is + $rC * 4;else:$pc += 4;Syntax jne $rA $rB $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$is + $rC * 4 > VM_MAX_RAM - 1 and the jump would be performed (i.e. $rA != $rB) Description Jump to the code instruction offset by imm if $rA is not equal to $rB. Operation if $rA != $rB:$pc = $is + imm * 4;else:$pc += 4;Syntax jnei $rA $rB immEncoding 0x00 rA rB i iNotes
Panic if:
$is + imm * 4 > VM_MAX_RAM - 1 and the jump would be performed (i.e. $rA != $rB) Description Jump to the code instruction offset by imm if $rA is not equal to $zero. Operation if $rA != $zero:$pc = $is + imm * 4;else:$pc += 4;Syntax jnzi $rA immEncoding 0x00 rA i i iNotes
Panic if:
$is + imm * 4 > VM_MAX_RAM - 1and the jump would be performed (i.e. $rA != $zero) Description Jump $rA + imm instructions backwards. Operation $pc -= ($rA + imm + 1) * 4;Syntax jmpb $rA immEncoding 0x00 rA i i iNotes
Panic if:
$pc - ($rA + imm + 1) * 4 < 0 Description Jump $rA + imm instructions forwards Operation $pc += ($rA + imm + 1) * 4;Syntax jmpf $rA immEncoding 0x00 rA i i iNotes
Panic if:
$pc + ($rA + imm + 1) * 4 > VM_MAX_RAM - 1 Description Jump $rB + imm instructions backwards if $rA !=Â $zero. Operation if $rA != $zero:$pc -= ($rB + imm + 1) * 4;else:$pc += 4;Syntax jnzb $rA $rB immEncoding 0x00 rA rB i iNotes
Panic if:
$pc - ($rB + imm + 1) * 4 < 0 Description Jump $rB + imm instructions forwards if $rA !=Â $zero. Operation if $rA != $zero:$pc += ($rB + imm + 1) * 4;else:$pc += 4;Syntax jnzf $rA $rB immEncoding 0x00 rA rB i iNotes
Panic if:
$pc + ($rB + imm + 1) * 4 > VM_MAX_RAM - 1 Description Jump $rC + imm instructions backwards if $rA !=Â $rB. Operation if $rA != $rB:$pc -= ($rC + imm + 1) * 4;else:$pc += 4;Syntax jneb $rA $rB $rC immEncoding 0x00 rA rB rC iNotes
Panic if:
$pc - ($rC + imm + 1) * 4 < 0 Description Jump $rC + imm instructions forwards if $rA !=Â $rB. Operation if $rA != $rB:$pc += ($rC + imm + 1) * 4;else:$pc += 4;Syntax jnef $rA $rB $rC immEncoding 0x00 rA rB rC iNotes
Panic if:
$pc + ($rC + imm + 1) * 4 > VM_MAX_RAM - 1 Description Returns from context with value $rA. Operation return($rA);Syntax ret $rAEncoding 0x00 rA - - -Notes
Append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.Returnidbyte[32]Contract ID of current context if in an internal context, zero otherwise. valuint64Value of register $rA. pcuint64Value of register $pc. isuint64Value of register $is.
If current context is external, append an additional receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.ScriptResultresultuint640gas_useduint64Gas consumed by the script.
If current context is external, cease VM execution and return $rA.
Returns from contract call, popping the call frame. Before popping perform the following operations.
Return the unused forwarded gas to the caller:
$cgas = $cgas + $fp->$cgas (add remaining context gas from previous context to current remaining context gas) Set the return value:
$ret = $rA $retl = 0 Then pop the call frame and restore all registers except $ggas, $cgas, $ret, $retl and $hp. Afterwards, set the following registers:
$pc = $pc + 4 (advance program counter from where we called) All these instructions advance the program counter $pc by 4 after performing their operation.
Description Allocate a number of bytes from the heap. Operation $hp = $hp - $rA;Syntax aloc $rAEncoding 0x00 rA - - -Notes Does not initialize memory.
Panic if:
$hp - $rA underflows $hp - $rA < $sp Description Extend the current call frame's stack. Operation $sp = $sp + $rASyntax cfei $rAEncoding 0x00 rA - - -Notes Does not initialize memory.
Panic if:
$sp + $rA overflows $sp + $rA > $hp Description Extend the current call frame's stack by an immediate value. Operation $sp = $sp + immSyntax cfei immEncoding 0x00 i i i iNotes Does not initialize memory.
Panic if:
$sp + imm overflows $sp + imm > $hp Description Shrink the current call frame's stack. Operation $sp = $sp - $rASyntax cfs $rAEncoding 0x00 $rA - - -Notes Does not clear memory.
Panic if:
$sp - $rA underflows $sp - $rA < $ssp Description Shrink the current call frame's stack by an immediate value. Operation $sp = $sp - immSyntax cfsi immEncoding 0x00 i i i iNotes Does not clear memory.
Panic if:
$sp - imm underflows $sp - imm < $ssp Description A byte is loaded from the specified address offset by imm. Operation $rA = MEM[$rB + imm, 1];Syntax lb $rA, $rB, immEncoding 0x00 rA rB i iNotes
Panic if:
Description A word is loaded from the specified address offset by imm. Operation $rA = MEM[$rB + (imm * 8), 8];Syntax lw $rA, $rB, immEncoding 0x00 rA rB i iNotes
Panic if:
$rA is a reserved register $rB + (imm * 8) + 8 overflows $rB + (imm * 8) + 8 > VM_MAX_RAM Description Clear bytes in memory. Operation MEM[$rA, $rB] = 0;Syntax mcl $rA, $rBEncoding 0x00 rA rB - -Notes
Panic if:
$rA + $rB overflows $rA + $rB > VM_MAX_RAM The memory range MEM[$rA, $rB] does not pass ownership check Description Clear bytes in memory. Operation MEM[$rA, imm] = 0;Syntax mcli $rA, immEncoding 0x00 rA i i iNotes
Panic if:
$rA + imm overflows $rA + imm > VM_MAX_RAM The memory range MEM[$rA, imm] does not pass ownership check Description Copy bytes in memory. Operation MEM[$rA, $rC] = MEM[$rB, $rC];Syntax mcp $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$rA + $rC overflows $rB + $rC overflows $rA + $rC > VM_MAX_RAM $rB + $rC > VM_MAX_RAM The memory ranges MEM[$rA, $rC] and MEM[$rB, $rC] overlap The memory range MEM[$rA, $rC] does not pass ownership check Description Copy bytes in memory. Operation MEM[$rA, imm] = MEM[$rB, imm];Syntax mcpi $rA, $rB, immEncoding 0x00 rA rB imm immNotes
Panic if:
$rA + imm overflows $rB + imm overflows $rA + imm > VM_MAX_RAM $rB + imm > VM_MAX_RAM The memory ranges MEM[$rA, imm] and MEM[$rB, imm] overlap The memory range MEM[$rA, imm] does not pass ownership check Description Compare bytes in memory. Operation $rA = MEM[$rB, $rD] == MEM[$rC, $rD];Syntax meq $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDNotes
Panic if:
$rA is a reserved register $rB + $rD overflows $rC + $rD overflows $rB + $rD > VM_MAX_RAM $rC + $rD > VM_MAX_RAM Description Push a set of registers from range 40..64 to the stack in order. Operation tmp=$sp;$sp+=popcnt(imm)*8;MEM[tmp,$sp]=registers[40..64].mask(imm)Syntax pshh immEncoding 0x00 i i i iNotes The immediate value is used as a bitmask for selecting the registers.
Panic if:
$sp + popcnt(imm)*8 overflows $sp + popcnt(imm)*8 > $hp Description Push a set of registers from range 16..40 to the stack in order. Operation tmp=$sp;$sp+=popcnt(imm)*8;MEM[tmp,$sp]=registers[16..40].mask(imm)Syntax pshl immEncoding 0x00 i i i iNotes The immediate value is used as a bitmask for selecting the registers.
Panic if:
$sp + popcnt(imm)*8 overflows $sp + popcnt(imm)*8 > $hp Description Pop to a set of registers from range 40..64 from the stack. Operation tmp=$sp-popcnt(imm)*8;registers[40..64].mask(imm)=MEM[tmp,$sp]$sp-=tmp;Syntax poph immEncoding 0x00 i i i iNotes The immediate value is used as a bitmask for selecting the registers.
Panic if:
$sp - popcnt(imm)*8 overflows $sp - popcnt(imm)*8 < $ssp Description Pop to a set of registers from range 16..40 from the stack. Operation tmp=$sp-popcnt(imm)*8;registers[16..40].mask(imm)=MEM[tmp,$sp]$sp-=tmp;Syntax poph immEncoding 0x00 i i i iNotes The immediate value is used as a bitmask for selecting the registers.
Panic if:
$sp - popcnt(imm)*8 overflows $sp - popcnt(imm)*8 < $ssp Description The least significant byte of $rB is stored at the address $rA offset by imm. Operation MEM[$rA + imm, 1] = $rB[7, 1];Syntax sb $rA, $rB, immEncoding 0x00 rA rB i iNotes
Panic if:
$rA + imm + 1 overflows $rA + imm + 1 > VM_MAX_RAM The memory range MEM[$rA + imm, 1] does not pass ownership check Description The value of $rB is stored at the address $rA offset by imm. Operation MEM[$rA + (imm * 8), 8] = $rB;Syntax sw $rA, $rB, immEncoding 0x00 rA rB i iNotes
Panic if:
$rA + (imm * 8) + 8 overflows $rA + (imm * 8) + 8 > VM_MAX_RAM The memory range MEM[$rA + (imm * 8), 8] does not pass ownership check All these instructions advance the program counter
$pc by
4 after performing their operation, except for
CALL ,
RETD and
RVRT .
Description Set $rA to the balance of asset ID at $rB for contract with ID at $rC. Operation $rA = balance(MEM[$rB, 32], MEM[$rC, 32]);Syntax bal $rA, $rB, $rCEncoding 0x00 rA rB rC -Effects Balance tree read Notes
Where helper balance(asset_id: byte[32], contract_id: byte[32]) -> uint64 returns the current balance of asset_id of contract with ID contract_id.
Panic if:
$rA is a reserved register $rB + 32 overflows $rB + 32 > VM_MAX_RAM $rC + 32 overflows $rC + 32 > VM_MAX_RAM Contract with ID MEM[$rC, 32] is not in tx.inputs Description Get Fuel block height. Operation $rA = blockheight();Syntax bhei $rAEncoding 0x00 rA - - -Notes
Panic if:
Description Get block header hash. Operation MEM[$rA, 32] = blockhash($rB);Syntax bhsh $rA $rBEncoding 0x00 rA rB - -Notes
Panic if:
$rA + 32 overflows $rA + 32 > VM_MAX_RAM The memory range MEM[$rA, 32] does not pass ownership check Block header hashes for blocks with height greater than or equal to current block height are zero (0x00**32).
Description Burn $rA coins of the $rB ID from the current contract. Operation burn($rA, $rB);Syntax burn $rA $rBEncoding 0x00 rA rB - -Notes $rB is a pointer to a 32 byte ID in memory.
The asset ID is constructed using the asset ID construction method.
Panic if:
$rB + 32 > VM_MAX_RAM Balance of asset ID from constructAssetID(MEM[$fp, 32], MEM[$rB, 32]) of output with contract ID MEM[$fp, 32] minus $rA underflows $fp == 0 (in the script context) For output with contract ID MEM[$fp, 32], decrease balance of asset ID constructAssetID(MEM[$fp, 32], MEM[$rB, 32]) by $rA.
This modifies the balanceRoot field of the appropriate output.
Append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.Burnsub_idbyte[32]Asset sub identifier MEM[$rB, $rB + 32]. contract_idbyte[32]Contract ID of the current context. valuint64Value of register $rA. pcuint64Value of register $pc. isuint64Value of register $is.
Description Call contract. Operation Syntax call $rA $rB $rC $rDEncoding 0x00 rA rB rC rDEffects External call Notes
There is a balanceOfStart(asset_id: byte[32]) -> uint32 helper that returns the memory address of the remaining free balance of asset_id. If asset_id has no free balance remaining, the helper panics.
Panic if:
$rA + 32 overflows $rC + 32 overflows Contract with ID MEM[$rA, 32] is not in tx.inputs Reading past MEM[VM_MAX_RAM - 1] In an external context, if $rB > MEM[balanceOfStart(MEM[$rC, 32]), 8] In an internal context, if $rB is greater than the balance of asset ID MEM[$rC, 32] of output with contract ID MEM[$fp, 32] Register $rA is a memory address from which the following fields are set (word-aligned):
bytes type value description 32 byte[32]toContract ID to call. 8 byte[8]param1First parameter. 8 byte[8]param2Second parameter.
$rB is the amount of coins to forward. $rC points to the 32-byte asset ID of the coins to forward. $rD is the amount of gas to forward. If it is set to an amount greater than the available gas, all available gas is forwarded.
Append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.Callfrombyte[32]Contract ID of current context if in an internal context, zero otherwise. tobyte[32]Contract ID of called contract. amountuint64Amount of coins to forward, i.e. $rB. asset_idbyte[32]Asset ID of coins to forward, i.e. MEM[$rC, 32]. gasuint64Gas to forward, i.e. min($rD, $cgas). param1uint64First parameter. param2uint64Second parameter. pcuint64Value of register $pc. isuint64Value of register $is.
For output with contract ID MEM[$rA, 32], increase balance of asset ID MEM[$rC, 32] by $rB. In an external context, decrease MEM[balanceOfStart(MEM[$rC, 32]), 8] by $rB. In an internal context, decrease asset ID MEM[$rC, 32] balance of output with contract ID MEM[$fp, 32] by $rB.
A
call frame is pushed at
$sp. In addition to filling in the values of the call frame, the following registers are set:
$fp = $sp (on top of the previous call frame is the beginning of this call frame) Set $ssp and $sp to the start of the writable stack area of the call frame. Set $pc and $is to the starting address of the code. $bal = $rB (forward coins) $cgas = $rD or all available gas (forward gas) This modifies the balanceRoot field of the appropriate output(s).
Description Get the coinbase contract id associated with the block proposer. Operation MEM[$rA, 32] = coinbase();Syntax cb $rAEncoding 0x00 rA - - -Notes
Panic if:
$rA + 32 overflows $rA + 32 > VM_MAX_RAM The memory range MEM[$rA, 32] does not pass ownership check Description Copy $rD bytes of code starting at $rC for contract with ID equal to the 32 bytes in memory starting at $rB into memory starting at $rA. Operation MEM[$rA, $rD] = code($rB, $rC, $rD);Syntax ccp $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDNotes If $rD is greater than the code size, zero bytes are filled in.
This is used only for reading and inspecting code of other contracts.
Use
LDC to load code for executing.
Panic if:
$rA + $rD overflows $rB + 32 overflows $rA + $rD > VM_MAX_RAM $rB + 32 > VM_MAX_RAM The memory range MEM[$rA, $rD] does not pass ownership check Contract with ID MEM[$rB, 32] is not in tx.inputs Description Set the 32 bytes in memory starting at $rA to the code root for contract with ID equal to the 32 bytes in memory starting at $rB. Operation MEM[$rA, 32] = coderoot(MEM[$rB, 32]);Syntax croo $rA, $rBEncoding 0x00 rA rB - -Notes
Panic if:
$rA + 32 overflows $rB + 32 overflows $rA + 32 > VM_MAX_RAM $rB + 32 > VM_MAX_RAM The memory range MEM[$rA, 32] does not pass ownership check Contract with ID MEM[$rB, 32] is not in tx.inputs Code root computation is defined
here .
Description Set $rA to the size of the code for contract with ID equal to the 32 bytes in memory starting at $rB. Operation $rA = codesize(MEM[$rB, 32]);Syntax csiz $rA, $rBEncoding 0x00 rA rB - -Notes
Panic if:
$rA is a reserved register $rB + 32 overflows $rB + 32 > VM_MAX_RAM Contract with ID MEM[$rB, 32] is not in tx.inputs Description Copy $rC bytes of code starting at $rB for contract with ID equal to the 32 bytes in memory starting at $rA into memory starting at $ssp. Operation MEM[$ssp, $rC] = code($rA, $rB, $rC);Syntax ldc $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes If $rC is greater than the code size, zero bytes are filled in.
Panic if:
$ssp + $rC overflows $rA + 32 overflows $ssp + $rC > VM_MAX_RAM $rA + 32 > VM_MAX_RAM $ssp + $rC >= $hp $rC > CONTRACT_MAX_SIZE Contract with ID MEM[$rA, 32] is not in tx.inputs Increment $fp->codesize, $ssp by $rC padded to word alignment. Then set $sp to $ssp.
This instruction can be used to concatenate the code of multiple contracts together. It can only be used when the stack area of the call frame is unused (i.e. prior to being used).
Description Log an event. This is a no-op. Operation log($rA, $rB, $rC, $rD);Syntax log $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDNotes
Append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.Logidbyte[32]Contract ID of current context if in an internal context, zero otherwise. val0uint64Value of register $rA. val1uint64Value of register $rB. val2uint64Value of register $rC. val3uint64Value of register $rD. pcuint64Value of register $pc. isuint64Value of register $is.
Description Log an event. This is a no-op. Operation logd($rA, $rB, $rC, $rD);Syntax logd $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDNotes
Append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.LogDataidbyte[32]Contract ID of current context if in an internal context, zero otherwise. val0uint64Value of register $rA. val1uint64Value of register $rB. ptruint64Value of register $rC. lenuint64Value of register $rD. digestbyte[32]Hash of MEM[$rC, $rD].pcuint64Value of register $pc. isuint64Value of register $is.
Logs the memory range MEM[$rC, $rD].
Panics if:
$rC + $rD overflows $rA + $rD > VM_MAX_RAM Description Mint $rA coins of the $rB ID from the current contract. Operation mint($rA, $rB);Syntax mint $rA $rBEncoding 0x00 rA rB - -Notes $rB is a pointer to a 32 byte ID in memory
The asset ID will be constructed using the asset ID construction method.
Panic if:
$rB + 32 > VM_MAX_RAM Balance of asset ID constructAssetID(MEM[$fp, 32], MEM[$rB]) of output with contract ID MEM[$fp, 32] plus $rA overflows $fp == 0 (in the script context) For output with contract ID MEM[$fp, 32], increase balance of asset ID constructAssetID(MEM[$fp, 32], MEM[$rB]) by $rA.
This modifies the balanceRoot field of the appropriate output.
Append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.Mintsub_idbyte[32]Asset sub identifier MEM[$rB, $rB + 32]. contract_idbyte[32]Contract ID of the current context. valuint64Value of register $rA. pcuint64Value of register $pc. isuint64Value of register $is.
Description Returns from context with value MEM[$rA, $rB]. Operation returndata($rA, $rB);Syntax retd $rA, $rBEncoding 0x00 rA rB - -Notes
Panic if:
$rA + $rB overflows $rA + $rB > VM_MAX_RAM Append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.ReturnDataidbyte[32]Contract ID of current context if in an internal context, zero otherwise. ptruint64Value of register $rA. lenuint64Value of register $rB. digestbyte[32]Hash of MEM[$rA, $rB].pcuint64Value of register $pc. isuint64Value of register $is.
If current context is a script, append an additional receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.ScriptResultresultuint640gas_useduint64Gas consumed by the script.
If current context is external, cease VM execution and return MEM[$rA, $rB].
Returns from contract call, popping the call frame. Before popping, perform the following operations.
Return the unused forwarded gas to the caller:
$cgas = $cgas + $fp->$cgas (add remaining context gas from previous context to current remaining context gas) Set the return value:
$ret = $rA $retl = $rB Then pop the call frame and restore all registers except $ggas, $cgas, $ret, $retl and $hp. Afterwards, set the following registers:
$pc = $pc + 4 (advance program counter from where we called) Description Halt execution, reverting state changes and returning value in $rA. Operation revert($rA);Syntax rvrt $rAEncoding 0x00 rA - - -Notes
Append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.Revertidbyte[32]Contract ID of current context if in an internal context, zero otherwise. valuint64Value of register $rA. pcuint64Value of register $pc. isuint64Value of register $is.
Then append an additional receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.ScriptResultresultuint641gas_useduint64Gas consumed by the script.
Cease VM execution and revert script effects. After a revert:
All OutputContract balanceRoot and stateRoot as on initialization. All OutputVariable to, amount, and asset_id of zero. Description Send a message to recipient address MEM[$rA, 32] from the MEM[$fp, 32] sender with message data MEM[$rB, $rC] and the $rD amount of base asset coins. Operation outputmessage(MEM[$fp, 32], MEM[$rA, 32], MEM[$rB, $rC], $rD);Syntax smo $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDEffects Output message Notes
There is a balanceOfStart(asset_id: byte[32]) -> uint32 helper that returns the memory address of the remaining free balance of asset_id. If asset_id has no free balance remaining, the helper panics.
Panic if:
$rA + 32 overflows $rB + $rC overflows $rA + 32 > VM_MAX_RAM $rB + $rC > VM_MAX_RAM $rC > MESSAGE_MAX_DATA_SIZE In an external context, if $rD > MEM[balanceOfStart(0), 8] In an internal context, if $rD is greater than the balance of asset ID 0 of output with contract ID MEM[$fp, 32] Append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.MessageOutsenderbyte[32]The address of the message sender: MEM[$fp, 32]. recipientbyte[32]The address of the message recipient: MEM[$rA, 32]. amountuint64Amount of base asset coins sent with message: $rD. noncebyte[32]The message nonce as described here . lenuint16Length of message data, in bytes: $rC. digestbyte[32]Hash of MEM[$rB, $rC].
In an external context, decrease MEM[balanceOfStart(0), 8] by $rD. In an internal context, decrease asset ID 0 balance of output with contract ID MEM[$fp, 32] by $rD. This modifies the balanceRoot field of the appropriate contract that had its' funds deducted.
Description A sequential series of 32 bytes is cleared from the current contract's state. Operation STATE[MEM[$rA, 32], 32 * $rC] = None;Syntax scwq $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$rA + 32 overflows $rA + 32 > VM_MAX_RAM $rB is a reserved register $fp == 0 (in the script context) Register $rB will be set to false if any storage slot in the requested range was already unset (default) and true if all the slots were set.
Description A word is read from the current contract's state. Operation $rA = STATE[MEM[$rC, 32]][0, 8];Syntax srw $rA, $rB, $rCEncoding 0x00 rA rB rC -Effects Storage read Notes Returns zero if the state element does not exist.
Panic if:
Register $rB will be set to false if the requested slot is unset (default) and true if it's set.
Description A sequential series of 32 bytes is read from the current contract's state. Operation MEM[$rA, 32 * rD] = STATE[MEM[$rC, 32], 32 * rD];Syntax srwq $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDEffects Storage read Notes Returns zero if the state element does not exist.
Panic if:
$rA + 32 * rD overflows $rA + 32 * rD > VM_MAX_RAM $rB is a reserved register $rC + 32 * rD overflows $rC + 32 * rD > VM_MAX_RAM The memory range MEM[$rA, 32 * rD] does not pass ownership check $fp == 0 (in the script context) Register $rB will be set to false if any storage slot in the requested range is unset (default) and true if all the slots are set.
Description A word is written to the current contract's state. Operation STATE[MEM[$rA, 32]][0, 8] = $rC;STATE[MEM[$rA, 32]][8, 24] = 0;Syntax sww $rA $rB $rCEncoding 0x00 rA rB rC -Effects Storage write Notes Additional gas is charged when a new storage slot is created.
Panic if:
$rA + 32 overflows $rA + 32 > VM_MAX_RAM $rB is a reserved register $fp == 0 (in the script context) The last 24 bytes of STATE[MEM[$rA, 32]] are set to 0. Register $rB will be set to the number of new slots written, i.e. 1 if the slot was previously unset, and 0 if it already contained a value.
Description A sequential series of 32 bytes is written to the current contract's state. Operation STATE[MEM[$rA, 32], 32 * $rD] = MEM[$rC, 32 * $rD];Syntax swwq $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDEffects Storage write Notes Additional gas is charged when for each new storage slot created.
Panic if:
$rA + 32 overflows $rB is a reserved register $rC + 32 * $rD overflows $rA + 32 > VM_MAX_RAM $rC + 32 * $rD > VM_MAX_RAM $fp == 0 (in the script context) Register $rB will be set to the number of storage slots that were previously unset, and were set by this operation.
Description Get timestamp of block at given height. Operation $rA = time($rB);Syntax time $rA, $rBEncoding 0x00 rA rB - -Notes
Panic if:
Gets the timestamp of the block at height
$rB. Time is in
TAI64 Icon Link format.
Description Transfer $rB coins with asset ID at $rC to contract with ID at $rA. Operation transfer(MEM[$rA, 32], $rB, MEM[$rC, 32]);Syntax tr $rA, $rB, $rCEncoding 0x00 rA rB rC -Effects Balance tree read, balance tree write Notes
There is a balanceOfStart(asset_id: byte[32]) -> uint32 helper that returns the memory address of the remaining free balance of asset_id. If asset_id has no free balance remaining, the helper panics.
Panic if:
$rA + 32 overflows $rC + 32 overflows $rA + 32 > VM_MAX_RAM $rC + 32 > VM_MAX_RAM Contract with ID MEM[$rA, 32] is not in tx.inputs In an external context, if $rB > MEM[balanceOfStart(MEM[$rC, 32]), 8] In an internal context, if $rB is greater than the balance of asset ID MEM[$rC, 32] of output with contract ID MEM[$fp, 32] $rB == 0 Append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.Transferfrombyte[32]Contract ID of current context if in an internal context, zero otherwise. tobyte[32]Contract ID of contract to transfer coins to. amountuint64Amount of coins transferred. asset_idbyte[32]asset ID of coins transferred. pcuint64Value of register $pc. isuint64Value of register $is.
For output with contract ID MEM[$rA, 32], increase balance of asset ID MEM[$rC, 32] by $rB. In an external context, decrease MEM[balanceOfStart(MEM[$rC, 32]), 8] by $rB. In an internal context, decrease asset ID MEM[$rC, 32] balance of output with contract ID MEM[$fp, 32] by $rB.
This modifies the balanceRoot field of the appropriate output(s).
Description Transfer $rC coins with asset ID at $rD to address at $rA, with output $rB. Operation transferout(MEM[$rA, 32], $rB, $rC, MEM[$rD, 32]);Syntax tro $rA, $rB, $rC, $rDEncoding 0x00 rA rB rC rDEffects Balance tree read, balance tree write Notes
There is a balanceOfStart(asset_id: byte[32]) -> uint32 helper that returns the memory address of the remaining free balance of asset_id. If asset_id has no free balance remaining, the helper panics.
Panic if:
$rA + 32 overflows $rD + 32 overflows $rA + 32 > VM_MAX_RAM $rD + 32 > VM_MAX_RAM $rB > tx.outputsCount In an external context, if $rC > MEM[balanceOfStart(MEM[$rD, 32]), 8] In an internal context, if $rC is greater than the balance of asset ID MEM[$rD, 32] of output with contract ID MEM[$fp, 32] $rC == 0 tx.outputs[$rB].type != OutputType.Variable tx.outputs[$rB].amount != 0 Append a receipt to the list of receipts, modifying tx.receiptsRoot:
name type description typeReceiptTypeReceiptType.TransferOutfrombyte[32]Contract ID of current context if in an internal context, zero otherwise. tobyte[32]Address to transfer coins to. amountuint64Amount of coins transferred. asset_idbyte[32]asset ID of coins transferred. pcuint64Value of register $pc. isuint64Value of register $is.
In an external context, decrease MEM[balanceOfStart(MEM[$rD, 32]), 8] by $rC. In an internal context, decrease asset ID MEM[$rD, 32] balance of output with contract ID MEM[$fp, 32] by $rC. Then set:
tx.outputs[$rB].to = MEM[$rA, 32] tx.outputs[$rB].amount = $rC tx.outputs[$rB].asset_id = MEM[$rD, 32] This modifies the balanceRoot field of the appropriate output(s).
All these instructions advance the program counter $pc by 4 after performing their operation.
Description The 64-byte public key (x, y) recovered from 64-byte signature starting at $rB on 32-byte message hash starting at $rC. Operation MEM[$rA, 64] = ecrecover_k1(MEM[$rB, 64], MEM[$rC, 32]);Syntax eck1 $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$rA + 64 overflows $rB + 64 overflows $rC + 32 overflows $rA + 64 > VM_MAX_RAM $rB + 64 > VM_MAX_RAM $rC + 32 > VM_MAX_RAM The memory range MEM[$rA, 64] does not pass ownership check Signatures and signature verification are specified
here .
If the signature cannot be verified, MEM[$rA, 64] is set to 0 and $err is set to 1, otherwise $err is cleared.
To get the address from the public key, hash the public key with
SHA-2-256 .
Description The 64-byte public key (x, y) recovered from 64-byte signature starting at $rB on 32-byte message hash starting at $rC. Operation MEM[$rA, 64] = ecrecover_r1(MEM[$rB, 64], MEM[$rC, 32]);Syntax ecr1 $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$rA + 64 overflows $rB + 64 overflows $rC + 32 overflows $rA + 64 > VM_MAX_RAM $rB + 64 > VM_MAX_RAM $rC + 32 > VM_MAX_RAM The memory range MEM[$rA, 64] does not pass ownership check Signatures and signature verification are specified
here .
If the signature cannot be verified, MEM[$rA, 64] is set to 0 and $err is set to 1, otherwise $err is cleared.
To get the address from the public key, hash the public key with
SHA-2-256 .
Description Verification recovered from 32-byte public key starting at $rA and 64-byte signature starting at $rB on 32-byte message hash starting at $rC. Operation ed19verify(MEM[$rA, 32], MEM[$rB, 64], MEM[$rC, 32]);Syntax ed19 $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$rA + 32 overflows $rB + 64 overflows $rC + 32 overflows $rA + 32 > VM_MAX_RAM $rB + 64 > VM_MAX_RAM $rC + 32 > VM_MAX_RAM Verification are specified
here .
If there is an error in verification, $err is set to 1, otherwise $err is cleared.
Description The keccak-256 hash of $rC bytes starting at $rB. Operation MEM[$rA, 32] = keccak256(MEM[$rB, $rC]);Syntax k256 $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$rA + 32 overflows $rB + $rC overflows $rA + 32 > VM_MAX_RAM $rB + $rC > VM_MAX_RAM The memory range MEM[$rA, 32] does not pass ownership check Description The SHA-2-256 hash of $rC bytes starting at $rB. Operation MEM[$rA, 32] = sha256(MEM[$rB, $rC]);Syntax s256 $rA, $rB, $rCEncoding 0x00 rA rB rC -Notes
Panic if:
$rA + 32 overflows $rB + $rC overflows $rA + 32 > VM_MAX_RAM $rB + $rC > VM_MAX_RAM The memory range MEM[$rA, 32] does not pass ownership check All these instructions advance the program counter $pc by 4 after performing their operation.
Description Call an external function that has full access to the VM state. Operation external(&mut vm, $rA, $rB, $rC, $rD)Syntax ecal $rA $rB $rC $rDEncoding 0x00 rA rB rC rDNotes Does nothing by default, but the VM user can define this to do anything.
This function provides an escape hatch from the VM, similar to ecall instruction of RISC-V. The suggested convention is to use $rA for "system call number", i.e. identifying the procedure to call, but all arguments can be used freely. The operation can modify the VM state freely, including writing to registers and memory. Again, the suggested convention is to use $rA for the return value and $err for any possible errors. However, these conventions can be ignored when necessary.
Panic if:
The external function panics. Description Set $flag to $rA. Operation $flag = $rA;Syntax flag $rAEncoding 0x00 rA - - -Notes
Panic if:
Any reserved flags are set Description Get metadata from memory. Operation Varies (see below). Syntax gm $rA, immEncoding 0x00 rA imm imm immNotes
Read metadata from memory. A convenience instruction to avoid manually extracting metadata.
name value description GM_IS_CALLER_EXTERNAL0x00001Get if caller is external. GM_GET_CALLER0x00002Get caller's contract ID. GM_GET_VERIFYING_PREDICATE0x00003Get index of current predicate. GM_GET_CHAIN_ID0x00004Get the value of CHAIN_ID
If imm == GM_IS_CALLER_EXTERNAL:
Panic if:
$fp == 0 (in an external context) Set $rA to true if parent is an external context, false otherwise.
If imm == GM_GET_CALLER:
Panic if:
$fp == 0 (in an external context) $fp->$fp == 0 (if parent context is external) Set $rA to $fp->$fp (i.e. $rA will point to the previous call frame's contract ID).
If imm == GM_GET_VERIFYING_PREDICATE:
Panic if:
not in a predicate context Set $rA to the index of the currently-verifying predicate.
Description Get transaction fields. Operation Varies (see below). Syntax gtf $rA, $rB, immEncoding 0x00 rA rB i iNotes
name immset $rA to GTF_TYPE0x001tx.typeGTF_SCRIPT_GAS_LIMIT0x002tx.scriptGasLimitGTF_SCRIPT_SCRIPT_LENGTH0x003tx.scriptLengthGTF_SCRIPT_SCRIPT_DATA_LENGTH0x004tx.scriptDataLengthGTF_SCRIPT_INPUTS_COUNT0x005tx.inputsCountGTF_SCRIPT_OUTPUTS_COUNT0x006tx.outputsCountGTF_SCRIPT_WITNESSES_COUNT0x007tx.witnessesCountGTF_SCRIPT_RECEIPTS_ROOT0x008Memory address of tx.receiptsRoot GTF_SCRIPT_SCRIPT0x009Memory address of tx.script GTF_SCRIPT_SCRIPT_DATA0x00AMemory address of tx.scriptData GTF_SCRIPT_INPUT_AT_INDEX0x00BMemory address of tx.inputs[$rB] GTF_SCRIPT_OUTPUT_AT_INDEX0x00CMemory address of t.outputs[$rB] GTF_SCRIPT_WITNESS_AT_INDEX0x00DMemory address of tx.witnesses[$rB] GTF_CREATE_BYTECODE_LENGTH0x100tx.bytecodeLengthGTF_CREATE_BYTECODE_WITNESS_INDEX0x101tx.bytecodeWitnessIndexGTF_CREATE_STORAGE_SLOTS_COUNT0x102tx.storageSlotsCountGTF_CREATE_INPUTS_COUNT0x103tx.inputsCountGTF_CREATE_OUTPUTS_COUNT0x104tx.outputsCountGTF_CREATE_WITNESSES_COUNT0x105tx.witnessesCountGTF_CREATE_SALT0x106Memory address of tx.salt GTF_CREATE_STORAGE_SLOT_AT_INDEX0x107Memory address of tx.storageSlots[$rB] GTF_CREATE_INPUT_AT_INDEX0x108Memory address of tx.inputs[$rB] GTF_CREATE_OUTPUT_AT_INDEX0x109Memory address of t.outputs[$rB] GTF_CREATE_WITNESS_AT_INDEX0x10AMemory address of tx.witnesses[$rB] GTF_INPUT_TYPE0x200tx.inputs[$rB].typeGTF_INPUT_COIN_TX_ID0x201Memory address of tx.inputs[$rB].txID GTF_INPUT_COIN_OUTPUT_INDEX0x202tx.inputs[$rB].outputIndexGTF_INPUT_COIN_OWNER0x203Memory address of tx.inputs[$rB].owner GTF_INPUT_COIN_AMOUNT0x204tx.inputs[$rB].amountGTF_INPUT_COIN_ASSET_ID0x205Memory address of tx.inputs[$rB].asset_id GTF_INPUT_COIN_TX_POINTER0x206Memory address of tx.inputs[$rB].txPointer GTF_INPUT_COIN_WITNESS_INDEX0x207tx.inputs[$rB].witnessIndexGTF_INPUT_COIN_MATURITY0x208tx.inputs[$rB].maturityGTF_INPUT_COIN_PREDICATE_LENGTH0x209tx.inputs[$rB].predicateLengthGTF_INPUT_COIN_PREDICATE_DATA_LENGTH0x20Atx.inputs[$rB].predicateDataLengthGTF_INPUT_COIN_PREDICATE0x20BMemory address of tx.inputs[$rB].predicate GTF_INPUT_COIN_PREDICATE_DATA0x20CMemory address of tx.inputs[$rB].predicateData GTF_INPUT_COIN_PREDICATE_GAS_USED0x20Dtx.inputs[$rB].predicateGasUsedGTF_INPUT_CONTRACT_TX_ID0x220Memory address of tx.inputs[$rB].txID GTF_INPUT_CONTRACT_OUTPUT_INDEX0x221tx.inputs[$rB].outputIndexGTF_INPUT_CONTRACT_BALANCE_ROOT0x222Memory address of tx.inputs[$rB].balanceRoot GTF_INPUT_CONTRACT_STATE_ROOT0x223Memory address of tx.inputs[$rB].stateRoot GTF_INPUT_CONTRACT_TX_POINTER0x224Memory address of tx.inputs[$rB].txPointer GTF_INPUT_CONTRACT_CONTRACT_ID0x225Memory address of tx.inputs[$rB].contractID GTF_INPUT_MESSAGE_SENDER0x240Memory address of tx.inputs[$rB].sender GTF_INPUT_MESSAGE_RECIPIENT0x241Memory address of tx.inputs[$rB].recipient GTF_INPUT_MESSAGE_AMOUNT0x242tx.inputs[$rB].amountGTF_INPUT_MESSAGE_NONCE0x243Memory address of tx.inputs[$rB].nonce GTF_INPUT_MESSAGE_WITNESS_INDEX0x244tx.inputs[$rB].witnessIndexGTF_INPUT_MESSAGE_DATA_LENGTH0x245tx.inputs[$rB].dataLengthGTF_INPUT_MESSAGE_PREDICATE_LENGTH0x246tx.inputs[$rB].predicateLengthGTF_INPUT_MESSAGE_PREDICATE_DATA_LENGTH0x247tx.inputs[$rB].predicateDataLengthGTF_INPUT_MESSAGE_DATA0x248Memory address of tx.inputs[$rB].data GTF_INPUT_MESSAGE_PREDICATE0x249Memory address of tx.inputs[$rB].predicate GTF_INPUT_MESSAGE_PREDICATE_DATA0x24AMemory address of tx.inputs[$rB].predicateData GTF_INPUT_MESSAGE_PREDICATE_GAS_USED0x24Btx.inputs[$rB].predicateGasUsedGTF_OUTPUT_TYPE0x300tx.outputs[$rB].typeGTF_OUTPUT_COIN_TO0x301Memory address of tx.outputs[$rB].to GTF_OUTPUT_COIN_AMOUNT0x302tx.outputs[$rB].amountGTF_OUTPUT_COIN_ASSET_ID0x303Memory address of tx.outputs[$rB].asset_id GTF_OUTPUT_CONTRACT_INPUT_INDEX0x304tx.outputs[$rB].inputIndexGTF_OUTPUT_CONTRACT_BALANCE_ROOT0x305Memory address of tx.outputs[$rB].balanceRoot GTF_OUTPUT_CONTRACT_STATE_ROOT0x306Memory address of tx.outputs[$rB].stateRoot GTF_OUTPUT_CONTRACT_CREATED_CONTRACT_ID0x307Memory address of tx.outputs[$rB].contractID GTF_OUTPUT_CONTRACT_CREATED_STATE_ROOT0x308Memory address of tx.outputs[$rB].stateRoot GTF_WITNESS_DATA_LENGTH0x400tx.witnesses[$rB].dataLengthGTF_WITNESS_DATA0x401Memory address of tx.witnesses[$rB].data GTF_POLICY_TYPES0x500tx.policies.policyTypesGTF_POLICY_GAS_PRICE0x501tx.policies[0x00].gasPriceGTF_POLICY_WITNESS_LIMIT0x502tx.policies[count_ones(0b11 & tx.policyTypes) - 1].witnessLimitGTF_POLICY_MATURITY0x503tx.policies[count_ones(0b111 & tx.policyTypes) - 1].maturityGTF_POLICY_MAX_FEE0x504tx.policies[count_ones(0b1111 & tx.policyTypes) - 1].maxFee
Panic if:
$rA is a reserved register imm is not one of the values listed above The value of $rB results in an out of bounds access for variable-length fields The input or output type does not match (OutputChange and OutputVariable count as OutputCoin) The requested policy type is not set for this transaction. For fixed-length fields, the value of $rB is ignored.