On 11/08/2016 12:36 PM, Richard Henderson wrote:
> On 11/07/2016 03:44 PM, Bastian Koppelmann wrote:
>> Converts a 32-bit floating point number to an unsigned int. The
>> result is rounded towards zero.
>>
>> Signed-off-by: Bastian Koppelmann <kbast...@mail.uni-paderborn.de>
>> ---
>> v1 -> v2:
>> - ftouz: Correctly convert the result from uint32 to f32
>>
>> target-tricore/fpu_helper.c | 43
>> +++++++++++++++++++++++++++++++++++++++++++
>> target-tricore/helper.h | 1 +
>> target-tricore/translate.c | 3 +++
>> 3 files changed, 47 insertions(+)
>>
>> diff --git a/target-tricore/fpu_helper.c b/target-tricore/fpu_helper.c
>> index 98fe947..f717b53 100644
>> --- a/target-tricore/fpu_helper.c
>> +++ b/target-tricore/fpu_helper.c
>> @@ -215,3 +215,46 @@ uint32_t helper_itof(CPUTriCoreState *env,
>> uint32_t arg)
>> }
>> return (uint32_t)f_result;
>> }
>> +
>> +uint32_t helper_ftouz(CPUTriCoreState *env, uint32_t arg)
>> +{
>> + float32 f_arg = make_float32(arg);
>> + uint32_t result;
>> + int32_t flags;
>> + result = float32_to_uint32_round_to_zero(f_arg, &env->fp_status);
>> +
>> + flags = f_get_excp_flags(env);
>> + if (flags) {
>> + if (float32_is_any_nan(f_arg)) {
>> + flags |= float_flag_invalid;
>> + result = 0;
>> + /* f_real(D[a]) < 0.0 */
>> + } else if (float32_lt_quiet(f_arg, 0.0, &env->fp_status)) {
>> + flags |= float_flag_invalid;
>> + result = 0;
>> + /* f_real(D[a]) > 2^32 -1 */
>> + } else if (float32_lt_quiet(0x4f800000, f_arg,
>> &env->fp_status)) {
>> + flags |= float_flag_invalid;
>> + result = 0xffffffff;
>> + } else {
>> + flags &= ~float_flag_invalid;
>> + }
>
> I don't understand this bit. Surely float_flag_invalid is already set
> by softfloat. And the bounding is done as well. What's up?
>
Consider 0x836d4e86 as an input which is clearly negative, however
float_flag_invalid is not set. The hardware on the other hand does set it.
Cheers,
Bastian
