Enum InstructionFragment 

pub(crate) enum InstructionFragment {
    Arithmetic(ArithmeticExpression),
    DeferredAddressing(SimpleSpan),
    Config(ConfigValue),
    PipeConstruct {
        index: SpannedSymbolOrLiteral,
        rc_word_span: SimpleSpan,
        rc_word_value: RegisterContaining,
    },
    Null(SimpleSpan),
}

Part of a TX-2 instruction.

In the M4 assembly language, each part is evaluated separately and then they are combined.

Variants

Arithmetic(ArithmeticExpression)

Arithmetic expressions are permitted in normal case according to the Users Handbook, but currently this implementation allows them in subscript/superscript too.

DeferredAddressing(SimpleSpan)

Insicates that the current instruction should use the deferred addressing mode.

The programmer indicates this with *. The programmer can also make use of deferred addressing by using the “pipe construct” (which is represented by InstructionFragment::PipeConstruct)

Config(ConfigValue)

A configuration syllable (specified either in superscript or with a ‖).

PipeConstruct

Described in section 6-2.8 “SPECIAL SYMBOLS” of the Users Handbook.

Fields

index: SpannedSymbolOrLiteral

rc_word_span: SimpleSpan

rc_word_value: RegisterContaining

Null(SimpleSpan)

Purely an implementation artifact.

Used by the assembler when parsing a CommaDelimitedFragment to represent the commas at the beginning or end of a part of the input program which gets parsed as an UntaggedProgramInstruction.

Implementations

impl InstructionFragment

fn symbol_uses( &self, block_id: BlockIdentifier, block_offset: Unsigned18Bit, ) -> impl Iterator<Item = Result<(SymbolName, SimpleSpan, SymbolUse), InconsistentSymbolUse>> + use<>

fn substitute_macro_parameters( &self, param_values: &MacroParameterBindings, on_missing: OnUnboundMacroParameter, macros: &BTreeMap<SymbolName, MacroDefinition>, ) -> Option<InstructionFragment>

fn allocate_rc_words<R: RcAllocator>( &mut self, explicit_symtab: &mut ExplicitSymbolTable, implicit_symtab: &mut ImplicitSymbolTable, rc_allocator: &mut R, ) -> Result<(), RcWordAllocationFailure>

Trait Implementations

impl Clone for InstructionFragment

fn clone(&self) -> InstructionFragment

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for InstructionFragment

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

Formats the value using the given formatter.

impl Evaluate for InstructionFragment

fn evaluate<R: RcUpdater>( &self, ctx: &mut EvaluationContext<'_, R>, scope: ScopeIdentifier, ) -> Result<Unsigned36Bit, EvaluationFailure>

impl From<(SimpleSpan, Script, Unsigned36Bit)> for InstructionFragment

fn from( (span, script, v): (SimpleSpan, Script, Unsigned36Bit), ) -> InstructionFragment

Converts to this type from the input type.

impl From<ArithmeticExpression> for InstructionFragment

fn from(expr: ArithmeticExpression) -> Self

Converts to this type from the input type.

impl PartialEq for InstructionFragment

fn eq(&self, other: &InstructionFragment) -> 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 Spanned for InstructionFragment

fn span(&self) -> SimpleSpan

impl Eq for InstructionFragment

impl StructuralPartialEq for InstructionFragment