Re: [Qemu-devel] [PATCH v8 08/16] target-or32: Add instruction translation

[Jia Liu]

On Wed, Jul 4, 2012 at 10:23 AM, Jia Liu <address@hidden> wrote:
> Hi Blue,
>
> On Wed, Jul 4, 2012 at 2:48 AM, Blue Swirl <address@hidden> wrote:
>> On Sun, Jul 1, 2012 at 2:45 AM, Jia Liu <address@hidden> wrote:
>>> +    switch (op0) {
>>> +    case 0x00:    /* l.j */
>>> +        LOG_DIS("l.j %d\n", N26);
>>> +    case 0x01:    /* l.jal */
>>> +        LOG_DIS("l.jal %d\n", N26);
>>> +    case 0x03:    /* l.bnf */
>>> +        LOG_DIS("l.bnf %d\n", N26);
>>> +    case 0x04:    /* l.bf */
>>> +        LOG_DIS("l.bf %d\n", N26);
>>> +
>>> +        gen_jump(dc, N26, 0, op0);
>>
>> The cases 0x00 to 0x03 will fall through to this case, calling LOG_DIS
>> one to four times.
>
> Sorry, I can't find a better path. Is this code OK?
>
>     switch (op0) {
>     case 0x00:    /* l.j */
>     case 0x01:    /* l.jal */
>     case 0x03:    /* l.bnf */
>     case 0x04:    /* l.bf */
>         LOG_DIS("l.j/l.jal/l.bnf/l.bf %d\n", N26);
>
>         gen_jump(dc, N26, 0, op0);
>

or is this code OK?

    switch (op0) {
    case 0x00:    /* l.j */
        LOG_DIS("l.j %d\n", N26);
        gen_jump(dc, N26, 0, op0);
        break;
    case 0x01:    /* l.jal */
        LOG_DIS("l.jal %d\n", N26);
        gen_jump(dc, N26, 0, op0);
        break;
    case 0x03:    /* l.bnf */
        LOG_DIS("l.bnf %d\n", N26);
        gen_jump(dc, N26, 0, op0);
        break;
    case 0x04:    /* l.bf */
        LOG_DIS("l.bf %d\n", N26);
        gen_jump(dc, N26, 0, op0);
        break;


>>> +
>>> +    case 0x11:    /* l.jr */
>>> +        LOG_DIS("l.jr r%d\n", rb);
>>> +    case 0x12:    /* l.jalr */
>>> +        LOG_DIS("l.jalr r%d\n", rb);
>>> +
>>> +        gen_jump(dc, 0, rb, op0);
>>
>> Also here.
>>
>
> And, this?
>
     case 0x11:    /* l.jr */
         gen_jump(dc, 0, rb, op0);
         break;
     case 0x12:    /* l.jalr */
         LOG_DIS("l.jr r%d\n", rb);
         gen_jump(dc, 0, rb, op0);
         break;

>>> +static void dec_sys(DisasContext *dc, uint32_t insn)
>>> +{
>>> +    uint32_t op0;
>>> +    /*uint32_t K16;*/
>>> +    op0 = field(insn, 16, 8);
>>> +    /*K16 = field(insn, 0, 16);*/
>>> +
>>> +    switch (op0) {
>>> +    case 0x000:    /* l.sys */
>>> +        /*LOG_DIS("l.sys %d\n", K16);*/
>>
>> Why commented out?
>
> When I build QEMU, I got a error msg like "unused var K16, treat
> warnings as errors".
> I didn't find a better way to handle it, so, commented it.
>
>>
>>> +        tcg_gen_movi_tl(cpu_pc, dc->pc);
>>> +        gen_exception(dc, EXCP_SYSCALL);
>>> +        dc->is_jmp = DISAS_UPDATE;
>>> +        break;
>>> +
>>> +    case 0x100:    /* l.trap */
>>> +        /*LOG_DIS("l.trap %d\n", K16);*/
>>
>> Ditto
>>
>
> And, commented it here.
>
>>> +        tcg_gen_movi_tl(cpu_pc, dc->pc);
>>> +        gen_exception(dc, EXCP_TRAP);
>>> +        break;
>>> +
>
> Regards,
> Jia.


Regards,
Jia.