Re: [Qemu-devel] [PATCH v4 14/31] arm/translate-a64: add FP16 FMULX/MLS/FMLA to simd_indexed

["Alex Bennée" <alex.bennee@linaro.org>]

Richard Henderson <richard.henderson@linaro.org> writes:

> On 02/27/2018 06:38 AM, Alex Bennée wrote:
>> @@ -11244,7 +11245,7 @@ static void disas_simd_indexed(DisasContext *s, uint32_t insn)
>>          }
>>          /* fall through */
>>      case 0x9: /* FMUL, FMULX */
>> -        if (!extract32(size, 1, 1)) {
>> +        if (size == 1) {
>>              unallocated_encoding(s);
>>              return;
>>          }
>
> This is still redundant, since size == 1 is handled...

doh!

will fix.

>
>> @@ -11256,18 +11257,34 @@ static void disas_simd_indexed(DisasContext *s, uint32_t insn)
>>      }
>>
>>      if (is_fp) {
>> -        /* low bit of size indicates single/double */
>> -        size = extract32(size, 0, 1) ? 3 : 2;
>> -        if (size == 2) {
>> +        /* convert insn encoded size to TCGMemOp size */
>> +        switch (size) {
>> +        case 2: /* single precision */
>> +            size = MO_32;
>>              index = h << 1 | l;
>> -        } else {
>> +            rm |= (m << 4);
>> +            break;
>> +        case 3: /* double precision */
>> +            size = MO_64;
>>              if (l || !is_q) {
>>                  unallocated_encoding(s);
>>                  return;
>>              }
>>              index = h;
>> +            rm |= (m << 4);
>> +            break;
>> +        case 0: /* half precision */
>> +            size = MO_16;
>> +            index = h << 2 | l << 1 | m;
>> +            is_fp16 = true;
>> +            if (arm_dc_feature(s, ARM_FEATURE_V8_FP16)) {
>> +                break;
>> +            }
>> +            /* fallthru */
>> +        default: /* unallocated */
>> +            unallocated_encoding(s);
>> +            return;
>>          }
>
> ... here.  But it's not wrong and I can clean this up along with the additional
> changes I need to make to this function for fcmla support.  So,
>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
>
>
> r~


--
Alex Bennée