Struct cranelift_codegen_meta::cdsl::formats::InstructionFormat

pub(crate) struct InstructionFormat {
    pub name: &'static str,
    pub num_value_operands: usize,
    pub has_value_list: bool,
    pub imm_fields: Vec<FormatField>,
    pub typevar_operand: Option<usize>,
}

Every instruction opcode has a corresponding instruction format which determines the number of operands and their kinds. Instruction formats are identified structurally, i.e., the format of an instruction is derived from the kinds of operands used in its declaration.

The instruction format stores two separate lists of operands: Immediates and values. Immediate operands (including entity references) are represented as explicit members in the InstructionData variants. The value operands are stored differently, depending on how many there are. Beyond a certain point, instruction formats switch to an external value list for storing value arguments. Value lists can hold an arbitrary number of values.

All instruction formats must be predefined in the meta shared/formats.rs module.

Fields

name: &'static str

Instruction format name in CamelCase. This is used as a Rust variant name in both the InstructionData and InstructionFormat enums.

num_value_operands: usize

has_value_list: bool

imm_fields: Vec<FormatField>

typevar_operand: Option<usize>

Index of the value input operand that is used to infer the controlling type variable. By default, this is 0, the first value operand. The index is relative to the values only, ignoring immediate operands.

Methods

impl InstructionFormat

pub fn imm_by_name(&self, name: &'static str) -> &FormatField

pub fn structure(&self) -> FormatStructure

Returns a tuple that uniquely identifies the structure.

Trait Implementations

impl Debug for InstructionFormat

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

Formats the value using the given formatter.

impl Display for InstructionFormat

fn fmt(&self, fmt: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.