Compiler Intrinsics
The Sway compiler supports a list of intrinsics that perform various low level operations that are useful for building libraries. Compiler intrinsics should rarely be used but are preferred over asm blocks because they are type-checked and are safer overall. Below is a list of all available compiler intrinsics:
__size_of_val<T>(val: T) -> u64
Description: Return the size of type T in bytes.
Constraints: None.
__size_of<T>() -> u64
Description: Return the size of type T in bytes.
Constraints: None.
__size_of_str_array<T>() -> u64
Description: Return the size of type T in bytes. This intrinsic differs from __size_of in the case of "string arrays" where the actual length in bytes of the string is returned without padding the byte size to the next word alignment. When T is not a "string array" 0 is returned.
Constraints: None.
__assert_is_str_array<T>()
Description: Throws a compile error if type T is not a "string array".
Constraints: None.
__to_str_array(s: str) -> str[N]
Description: Converts a "string slice" to "string array" at compile time. Parameter "s" must be a string literal.
Constraints: None.
__is_reference_type<T>() -> bool
Description: Returns true if T is a reference type and false otherwise.
Constraints: None.
__is_str_array<T>() -> bool
Description: Returns true if T is a string array and false otherwise.
Constraints: None.
__eq<T>(lhs: T, rhs: T) -> bool
Description: Returns whether lhs and rhs are equal.
Constraints: T is bool, u8, u16, u32, u64, u256, b256 or raw_ptr.
__gt<T>(lhs: T, rhs: T) -> bool
Description: Returns whether lhs is greater than rhs.
Constraints: T is u8, u16, u32, u64, u256, b256.
__lt<T>(lhs: T, rhs: T) -> bool
Description: Returns whether lhs is less than rhs.
Constraints: T is u8, u16, u32, u64, u256, b256.
__gtf<T>(index: u64, tx_field_id: u64) -> T
Description: Returns transaction field with ID tx_field_id at index index, if applicable. This is a wrapper around FuelVM's gtf instruction. The resulting field is cast to T.
Constraints: None.
__addr_of<T>(val: T) -> raw_ptr
Description: Returns the address in memory where val is stored.
Constraints: T is a reference type.
__state_load_word(key: b256) -> u64
Description: Reads and returns a single word from storage at key key.
Constraints: None.
__state_load_quad(key: b256, ptr: raw_ptr, slots: u64) -> bool
Description: Reads slots number of slots (b256 each) from storage starting at key key and stores them in memory starting at address ptr. Returns a Boolean describing whether all the storage slots were previously set.
Constraints: None.
__state_store_word(key: b256, val: u64) -> bool
Description: Stores a single word val into storage at key key. Returns a Boolean describing whether the store slot was previously set.
Constraints: None.
__state_store_quad(key: b256, ptr: raw_ptr, slots: u64) -> bool
Description: Stores slots number of slots (b256 each) starting at address ptr in memory into storage starting at key key. Returns a Boolean describing whether the first storage slot was previously set.
Constraints: None.
__log<T>(val: T)
Description: Logs value val.
Constraints: None.
__add<T>(lhs: T, rhs: T) -> T
Description: Adds lhs and rhs and returns the result.
Constraints: T is an integer type, i.e. u8, u16, u32, u64, u256.
__sub<T>(lhs: T, rhs: T) -> T
Description: Subtracts rhs from lhs.
Constraints: T is an integer type, i.e. u8, u16, u32, u64, u256.
__mul<T>(lhs: T, rhs: T) -> T
Description: Multiplies lhs by rhs.
Constraints: T is an integer type, i.e. u8, u16, u32, u64, u256.
__div<T>(lhs: T, rhs: T) -> T
Description: Divides lhs by rhs.
Constraints: T is an integer type, i.e. u8, u16, u32, u64, u256.
__and<T>(lhs: T, rhs: T) -> T
Description: Bitwise AND lhs and rhs.
Constraints: T is an integer type, i.e. u8, u16, u32, u64, u256, b256.
__or<T>(lhs: T, rhs: T) -> T
Description: Bitwise OR lhs and rhs.
Constraints: T is an integer type, i.e. u8, u16, u32, u64, u256, b256.
__xor<T>(lhs: T, rhs: T) -> T
Description: Bitwise XOR lhs and rhs.
Constraints: T is an integer type, i.e. u8, u16, u32, u64, u256, b256.
__mod<T>(lhs: T, rhs: T) -> T
Description: Modulo of lhs by rhs.
Constraints: T is an integer type, i.e. u8, u16, u32, u64, u256.
__rsh<T>(lhs: T, rhs: u64) -> T
Description: Logical right shift of lhs by rhs.
Constraints: T is an integer type, i.e. u8, u16, u32, u64, u256, b256.
__lsh<T>(lhs: T, rhs: u64) -> T
Description: Logical left shift of lhs by rhs.
Constraints: T is an integer type, i.e. u8, u16, u32, u64, u256, b256.
__revert(code: u64)
Description: Reverts with error code code.
Constraints: None.
__ptr_add(ptr: raw_ptr, offset: u64)
Description: Adds offset to the raw value of pointer ptr.
Constraints: None.
__ptr_sub(ptr: raw_ptr, offset: u64)
Description: Subtracts offset to the raw value of pointer ptr.
Constraints: None.
__smo<T>(recipient: b256, data: T, coins: u64)
Description: Sends a message data of arbitrary type T and coins amount of the base asset to address recipient.
Constraints: None.
__not(op: T) -> T
Description: Bitwise NOT of op
Constraints: T is an integer type, i.e. u8, u16, u32, u64, u256, b256.
__jmp_mem()
Description: Jumps to MEM[$hp].
Constraints: None.
__slice(item: &[T; N], start: u64, end: u64) -> &[T]
__slice(item: &[T], start: u64, end: u64) -> &[T]
__slice(item: &mut [T; N], start: u64, end: u64) -> &mut [T]
__slice(item: &mut [T], start: u64, end: u64) -> &mut [T]
Description: Slices an array or another slice.
This intrinsic returns a reference to a slice containing the range of elements inside item.
The mutability of reference is defined by the first parameter mutability.
Runtime bound checks are not generated, and must be done manually when and where appropriated. Compile time bound checks are done when possible.
Constraints:
itemis an array or a slice;- when
startis a literal, it must be smaller thanitemlength; - when
endis a literal, it must be smaller than or equal toitemlength; endmust be greater than or equal tostart
__elem_at(item: &[T; N], index: u64) -> &T
__elem_at(item: &[T], index: u64) -> &T
__elem_at(item: &mut [T; N], index: u64) -> &mut T
__elem_at(item: &mut [T], index: u64) -> &mut T
Description: Returns a reference to the indexed element. The mutability of reference is defined by the first parameter mutability.
Runtime bound checks are not generated, and must be done manually when and where appropriated. Compile time bound checks are done when possible.
Constraints:
itemis a reference to an array or a reference to a slice;- when
indexis a literal, it must be smaller thanitemlength;