Le 27/06/2017 à 22:00, Richard Henderson a écrit :
> On 06/27/2017 12:12 PM, Laurent Vivier wrote:
>> case 3: /* Ordered Greater than or Equal Z || !(A || N) */
>> case 19: /* Greater than or Equal Z || !(A || N) */
>> + g_assert(FPSR_CC_A == (FPSR_CC_N >> 3));
>> + c->v1 = tcg_temp_new();
>> + c->g1 = 0;
>> + tcg_gen_shli_i32(c->v1, fpsr, 3);
>> + tcg_gen_or_i32(c->v1, c->v1, fpsr);
>> + tcg_gen_xori_i32(c->v1, c->v1, FPSR_CC_N);
>> + tcg_gen_andi_i32(c->v1, c->v1, FPSR_CC_N | FPSR_CC_Z);
>> + c->tcond = TCG_COND_NE;
>
> Still with the unmasked shift.
>
> tcg_gen_not_i32(c->v1, fpsr);
> tcg_gen_andi_i32(c->v1, c->v1, FPSR_CC_A | FPSR_CC_N);
We want to compute !(A || N), but I think this is (!A || !N)
> tcg_gen_andi_i32(fpsr, fpsr, FPSR_CC_Z);
> tcg_gen_or_i32(c->v1, c->v1, fpsr);
So we have Z || !A || !N
Do you think we can do better than:
tcg_gen_andi_i32(c->v1, fpsr, FPSR_CC_A);
tcg_gen_shli_i32(c->v1, c->v1,
ctz32(FPSR_CC_N) - ctz32(FPSR_CC_A));
tcg_gen_andi_i32(fpsr, fpsr, FPSR_CC_Z | FPSR_CC_N);
tcg_gen_or_i32(c->v1, c->v1, fpsr);
tcg_gen_xori_i32(c->v1, c->v1, FPSR_CC_N);
Thanks,
Laurent
