Re: [Qemu-devel] [PATCH v2 10/14] tcg: Introduce temp_load

[Richard Henderson <rth@twiddle.net>]

On 12/31/2015 03:33 AM, Aurelien Jarno wrote:
>> -            if (ts->val_type == TEMP_VAL_REG) {
>> -                tcg_out_st(s, ts->type, ts->reg, TCG_REG_CALL_STACK, stack_offset);
>> -            } else if (ts->val_type == TEMP_VAL_MEM) {
>> -                reg = tcg_reg_alloc(s, tcg_target_available_regs[ts->type], 
>> -                                    s->reserved_regs);
>> -                /* XXX: not correct if reading values from the stack */
> 
> Shouldn't we keep this comment by moving it to temp_load?

No, because I believe the comment to be inaccurate.

> 
>> -                tcg_out_ld(s, ts->type, reg, ts->mem_base->reg, ts->mem_offset);
>> -                tcg_out_st(s, ts->type, reg, TCG_REG_CALL_STACK, stack_offset);
>> -            } else if (ts->val_type == TEMP_VAL_CONST) {
>> -                reg = tcg_reg_alloc(s, tcg_target_available_regs[ts->type], 
>> -                                    s->reserved_regs);
>> -                /* XXX: sign extend may be needed on some targets */
> 
> Same here.
> 
>> -                tcg_out_movi(s, ts->type, reg, ts->val);

Likewise.  If the target needs sign-extend, it will do it here in movi given
the type.

>> -                tcg_out_st(s, ts->type, reg, TCG_REG_CALL_STACK, stack_offset);
>> -            } else {
>> -                tcg_abort();
>> -            }
>> +            temp_load(s, ts, tcg_target_available_regs[ts->type],
>> +                      s->reserved_regs);
>> +            tcg_out_st(s, ts->type, ts->reg, TCG_REG_CALL_STACK, stack_offset);
>>          }
>>  #ifndef TCG_TARGET_STACK_GROWSUP
>>          stack_offset += sizeof(tcg_target_long);
>> @@ -2193,18 +2180,19 @@ static void tcg_reg_alloc_call(TCGContext *s, int nb_oargs, int nb_iargs,
>>              ts = &s->temps[arg];
>>              reg = tcg_target_call_iarg_regs[i];
>>              tcg_reg_free(s, reg);
>> +
>>              if (ts->val_type == TEMP_VAL_REG) {
>>                  if (ts->reg != reg) {
>>                      tcg_out_mov(s, ts->type, reg, ts->reg);
>>                  }
>> -            } else if (ts->val_type == TEMP_VAL_MEM) {
>> -                tcg_out_ld(s, ts->type, reg, ts->mem_base->reg, ts->mem_offset);
>> -            } else if (ts->val_type == TEMP_VAL_CONST) {
>> -                /* XXX: sign extend ? */
> 
> And here.
> 
>> -                tcg_out_movi(s, ts->type, reg, ts->val);

Likewise.


r~