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Код: Выделить всё

// JMP (cond) target
// cond: always, !x, x--, !y, y--, x != y, pin, !osre
// target: instruction address to jump to.
consteval bool processJmp()
{
    uint16_t instr = 0x0000;

    if (check("!")) // !x, !y, !osre
    {
        if      (check("x"))    instr |= 1 << 5;    // !x
        else if (check("y"))    instr |= 3 << 5;    // !y
        else if (check("osre")) instr |= 7 << 5;    // !osre
        else return Error("unexpected identifier ...");
        check(",");
    }
    else if (check("x"))
    {
        if (check("--"))
        {
            instr |= 2 << 5;    // x--
        }
        else if (check("!="))
        {
            if (check("y")) instr |= 5 << 5;    // x != y
            else return Error("expect 'x != y'");
        }
        else return Error("expect 'x--'");
        check(",");
    }
    else if (check("y"))
    {
        if (check("--")) instr |= 4 << 5;   // y--
        else return Error("expect 'y--'");
        check(",");
    }
    else if (check("pin"))
    {
        instr |= 6 << 5;    // pin
        check(",");
    }

    auto tok = getToken();
    if (tok.isText())
    {   // Label
        auto* label = findLabel(tok);
        if (label)
            instr |= label->addr;
        else
            jmpPatch.push({ tok.str, (int)code.size, line });
    }
    else if (tok.isNumber())
    {
        instr |= tok.value;
        if (tok.value > maxJmpValue)
        {
            maxJmpValue = tok.value;
            maxJmpLine  = line;
        }
    }
    else return Error("expect label or number.");

    return processSideDelay(instr);
}

// (side k) ([k])
consteval bool processSideDelay(uint16_t instr)
{
    bool hasSide = check("side");

    if (!sideSetOptional && sideSet && !hasSide) return Error("instruction requires 'side' to specify side set value.");
    
    if (hasSide)
    {
        int value = matchNumber(0, powf(2, sideSet) - 1, "side set value is out of range.");
        if (error) return false;
        instr |= value << (8 + 5 - sideSet - sideSetOptional) | (sideSetOptional << 12);
    }

    if (!check("["))
    {
        code.push(instr);
        return true;
    }

    int value = matchNumber(0, powf(2, 5 - sideSet - sideSetOptional) - 1, "instruction delay is out of range.");
    if (error) return false;
    code.push(instr | uint16_t(value << 8));

    if (!match("]", "expect ']'.")) return false;

    return true;
}