Enum Overflow 

#[repr(u8)]
pub enum Overflow {
    Error = 0,
    Wrap = 1,
    Trap = 2,
    Promote = 3,
}

The overflow policy: what integer add, sub, mul, neg, abs, signed MIN / -1, and int_cast do when the exact result does not fit.

Promote exists for dynamic-value operations only (OPS §2, added for Mox/PHP): it is valid only where the result register is dyn. ModuleBuilder refuses it on a statically typed destination it can see, and the verifier (v0.5) refuses it everywhere else.

Examples

use bytecode_lang::Overflow;

assert_eq!(Overflow::default(), Overflow::Error);
assert_eq!(Overflow::Wrap.to_string(), "wrap");
assert_eq!(Overflow::from_code(3), Some(Overflow::Promote));

Variants

Error = 0

Raise ArithOverflow (E0001) through the language’s error model.

Wrap = 1

Two’s-complement wrap-around; never an error.

Trap = 2

Abort the program with ArithOverflow (E0001); not catchable.

Promote = 3

The result is the f64 nearest the exact mathematical result (ties to even), as PHP does for PHP_INT_MAX + 1. Dynamic results only.

Implementations

impl Overflow

pub const ALL: &'static [Overflow]

Every value, in code order.

pub const fn from_code(code: u8) -> Option<Self>

The value with this stable code, or None if no value has it.

pub const fn code(self) -> u8

The stable code this value is encoded as.

pub const fn name(self) -> &'static str

The lowercase name the disassembler prints.

Trait Implementations

impl Clone for Overflow

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Overflow

impl Debug for Overflow

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Overflow

fn default() -> Self

Returns the “default value” for a type.

impl Display for Overflow

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Overflow

impl Hash for Overflow

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Overflow

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

fn clamp_to<R>(self, range: R) -> Self

where Self: Sized, R: ClampBounds<Self>,

🔬This is a nightly-only experimental API. (clamp_to)

Restrict a value to a certain range.

impl PartialEq for Overflow

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl PartialOrd for Overflow

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for Overflow