Enum midenc_hir::Overflow

pub enum Overflow {
    Unchecked,
    Checked,
    Wrapping,
    Overflowing,
}

This enumeration represents the various ways in which arithmetic operations can be configured to behave when either the operands or results over/underflow the range of the integral type.

Always check the documentation of the specific instruction involved to see if there are any specific differences in how this enum is interpreted compared to the default meaning of each variant.

Variants

Unchecked

Typically, this means the operation is performed using the equivalent field element operation, rather than a dedicated operation for the given type. Because of this, the result of the operation may exceed that of the integral type expected, but this will not be caught right away.

It is the callers responsibility to ensure that resulting value is in range.

Checked

The operation will trap if the operands, or the result, is not valid for the range of the integral type involved, e.g. u32.

Wrapping

The operation will wrap around, depending on the range of the integral type. For example, given a u32 value, this is done by applying mod 2^32 to the result.

Overflowing

The result of the operation will be computed as in [Wrapping], however in addition to the result, this variant also pushes a value on the stack which represents whether or not the operation over/underflowed; either 1 if over/underflow occurred, or 0 otherwise.

Implementations

impl Overflow

pub fn is_unchecked(&self) -> bool

Returns true if overflow is unchecked

pub fn is_checked(&self) -> bool

Returns true if overflow will cause a trap

pub fn is_overflowing(&self) -> bool

Returns true if overflow will add an extra boolean on top of the stack

Trait Implementations

impl Clone for Overflow

fn clone(&self) -> Overflow

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Overflow

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

Formats the value using the given formatter.

impl Default for Overflow

fn default() -> Overflow

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 PartialEq for Overflow

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Overflow

impl Eq for Overflow

impl StructuralPartialEq for Overflow