Function encode_call

crates/asm-to-binary/src/assembler/encode.rs:343–369

Encode `call symbol` -> `auipc ra, %pcrel_hi(symbol); jalr ra, ra, %pcrel_lo(symbol)`.

(
    sec: &mut SectionData,
    symbol: &str,
    current_addr: u64,
    symbols: &super::symbol_table::SymbolTable,
    section_bases: &std::collections::HashMap<SectionKind, u64>,
    relocations: 

    section_name: &str,
    symbols: &super::symbol_table::SymbolTable,
) -> Result<u32, AssemblerError> {
    let target_addr = resolve_section_local(target, section_name, symbols)
        .ok_or_else(|| AssemblerError::new(format!("undefined label `{target}`")))?;

    let offset = (target_addr as i64) - (site_local as i64);
    if offset & 1 != 0 {
        return Err(AssemblerError::new(format!(
            "jump to `{target}` has odd offset {offset}"
        )));
    }
    if !(-1_048_576..=1_048_574).contains(&offset) {
        return Err(AssemblerError::new(format!(
            "jump to `{target}` offset {offset} out of J-type range"
        )));
    }

    Ok(RealInstruction::Jal(JalInst::new(rd, offset as i32)).encode())
}

fn push_u32(sec: &mut SectionData, word: u32, current_addr: &mut u64) {
    sec.push_u32_le(word);
    *current_addr += 4;
}

// --- Pseudo-instruction encoding with symbol relocation ---

// Split a PC-relative byte offset into (hi20, lo12) for AUIPC+lo pairs.
fn pcrel_split(offset: i64) -> (i32, i32) {
    let lo12 = ((offset & 0xFFF) as i32).wrapping_sub(if offset & 0x800 != 0 { 0x1000 } else { 0 });
    let hi20 = ((offset - lo12 as i64) >> 12) as i32;