Function parse

crates/asm-to-binary/src/assembler/parser.rs:44–76

Convert a `RvInstruction` stream to a typed `AsmToken` stream. Tokens that cannot be parsed are emitted as `AsmToken::Comment` with the raw text so nothing is silently lost -- the caller can choose to error on those.

(tokens: &[RvInstruction])

pub fn parse(tokens: &[RvInstruction]) -> Vec<AsmToken> {
    let mut out = Vec::with_capacity(tokens.len());
    for tok in tokens {
        match tok {
            RvInstruction::Real(inst) => out.push(AsmToken::Real(inst.clone())),
            RvInstruction::Pseudo(p) => match p {
                // Keep symbol-bearing pseudos unresolved so pass-2 can
                // either resolve them immediately or emit relocation records.
                PseudoInstruction::Call { symbol } => out.push(AsmToken::Call {
                    symbol: symbol.clone(),
                }),
                PseudoInstruction::Tail { symbol } => out.push(AsmToken::Tail {
                    symbol: symbol.clone(),
                }),
                PseudoInstruction::La { rd, symbol } => out.push(AsmToken::La {
                    rd: *rd,
                    symbol: symbol.clone(),
                }),
                _ => {
                    for real in p.expand() {
                        out.push(AsmToken::Real(real));
                    }
                }
            },
            RvInstruction::Label(name) => out.push(AsmToken::Label(name.clone())),
            RvInstruction::Comment(_) => out.push(AsmToken::Comment),
            RvInstruction::SourceLoc { file, line } => out.push(AsmToken::Loc {
                file: file.clone(),
                line: *line,
            }),
            RvInstruction::Directive(raw) => {
                parse_directive_or_instruction(raw, &mut out);
            }
        }
    }
    out
}