Re: [Qemu-devel] [PATCH 2/4] tcg/aarch64: implement new TCG target for aarch64

[Claudio Fontana <claudio.fontana@huawei.com>]

On 23.05.2013 18:39, Peter Maydell wrote:
> On 23 May 2013 09:18, Claudio Fontana <claudio.fontana@huawei.com> wrote:
>>
>> add preliminary support for TCG target aarch64.
> 
> Richard's handling the technical bits of the review, so
> just some minor style nits here.
> 
> I tested this on the foundation model and was able to boot
> a 32-bit-ARM kernel.
> 
>> +static inline void reloc_pc19(void *code_ptr, tcg_target_long target)
>> +{
>> +    tcg_target_long offset; uint32_t insn;
>> +    offset = (target - (tcg_target_long)code_ptr) / 4;
>> +    offset &= 0x07ffff;
>> +    /* read instruction, mask away previous PC_REL19 parameter contents,
>> +       set the proper offset, then write back the instruction. */
>> +    insn = *(uint32_t *)code_ptr;
>> +    insn = (insn & 0xff00001f) | offset << 5; /* lower 5 bits = condition */
> 
> You can say
>     insn = deposit32(insn, 5, 19, offset);
> here rather than doing
>     offset &= 0x07ffff;
>     insn = (insn & 0xff00001f) | offset << 5;
> 
> (might as well also use deposit32 for consistency in the pc26 function.)

Ok, I'll make use of it.

>> +static inline enum aarch64_ldst_op_data
>> +aarch64_ldst_get_data(TCGOpcode tcg_op)
>> +{
>> +    switch (tcg_op) {
>> +    case INDEX_op_ld8u_i32: case INDEX_op_ld8s_i32:
>> +    case INDEX_op_ld8u_i64: case INDEX_op_ld8s_i64:
>> +    case INDEX_op_st8_i32: case INDEX_op_st8_i64:
> 
> One case per line, please (here and elsewhere).

Will comply.

>> +static inline void tcg_out_call(TCGContext *s, tcg_target_long target)
>> +{
>> +    tcg_target_long offset;
>> +
>> +    offset = (target - (tcg_target_long)s->code_ptr) / 4;
>> +
>> +    if (offset <= -0x02000000 || offset >= 0x02000000) { /* out of 26bit rng */
>> +        tcg_out_movi64(s, TCG_REG_TMP, target);
>> +        tcg_out_callr(s, TCG_REG_TMP);
>> +
> 
> Stray blank line.

I should remove this \n I assume. Ok.

>> +    case INDEX_op_mov_i64: ext = 1;
> 
> Please don't put code on the same line as a case statement.
> Also fall-through cases should have an explicit /* fall through */
> comment (except in the case where there is no code at all
> between one case statement and the next).

Will change for the next version.

> thanks
> -- PMM
> 

Thank you,

Claudio