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// https://github.com/micropython/micropython/blob/1b89c503db690967d50699abe0bfa942f6f6b15e/ports/qemu/mcu/rv32/interrupts.c#L131

const char *lookup_cause(uint32_t mcause) {
    if (mcause & 0x80000000) {
        switch (mcause & 0x7FFFFFFF) {
            case 1:
                return exception_causes[1];
            case 3:
                return exception_causes[2];
            case 5:
                return exception_causes[3];
            case 7:
                return exception_causes[4];
            case 9:
                return exception_causes[5];
            case 11:
                return exception_causes[6];
            default:
                return (mcause >= 16) ?
                       exception_causes[7] :
                       exception_causes[0];
        }
    }

    switch (mcause) {
        case 0:
            return exception_causes[8];
        case 1:
            return exception_causes[9];
        case 2:
            return exception_causes[10];
        case 3:
            return exception_causes[11];
        case 4:
            return exception_causes[12];
        case 5:
            return exception_causes[13];
        case 6:
            return exception_causes[14];
        case 7:
            return exception_causes[15];
        case 8:
            return exception_causes[16];
        case 9:
            return exception_causes[17];
        case 11:
            return exception_causes[18];
        case 12:
            return exception_causes[19];
        case 13:
            return exception_causes[20];
        case 15:
            return exception_causes[21];
        default: {
            if ((mcause >= 24 && mcause <= 31) ||
                (mcause >= 48 && mcause <= 63)) {
                return exception_causes[22];
            }

            return exception_causes[0];
        }
    }
}