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Re: PATCH: PR target/49142: Invalid 8bit register operand


On Wed, May 25, 2011 at 6:20 PM, H.J. Lu <hjl.tools@gmail.com> wrote:

>>>>> We are working on a new optimization, which turns off TARGET_MOVX.
>>>>> GCC generates:
>>>>>
>>>>> movb %ah, %dil
>>>>>
>>>>> But %ah can only be used with %[abcd][hl]. ?This patch adds QIreg_operand
>>>>> and uses it in *movqi_extv_1_rex64/*movqi_extzv_2_rex64. ?OK for trunk
>>>>> if there is no regression? and Replace
>> ? ? ? q_regs_operand with QIreg_operand.
>> ? ? ? (
>>>>
>>>> If this is the case, then please change "q_regs_operand" predicate to
>>>> accept just QI_REG_P registers.
>>>>
>>>
>>> I thought about it. ?It is a problem only with %[abcd]h. ?I am not sure if
>>> changing q_regs_operand to ?accept just QI_REG_P registers will negatively
>>> impact
>>
>> I see. The patch is OK then, but for consistency, please change the
>> predicate of *movqi_extv_1*movqi_extzv_2 as well. Oh, and the
>> "register_operand" check in "type" calculation can be removed.
>>
>> Thanks,
>> Uros.
>>
>
> This is what I checked in.
>
> Thanks.
>
> --
> H.J.
> ---
> 2011-05-25 ?H.J. Lu ?<hongjiu.lu@intel.com>
>
> ? ? ? ?PR target/49142
> ? ? ? ?* config/i386/i386.md (*movqi_extv_1_rex64): Remove
> ? ? ? ?"register_operand" check and replace q_regs_operand with
> ? ? ? ?QIreg_operand in "type" calculation.
> ? ? ? ?(*movqi_extv_1): Likewise.
> ? ? ? ?(*movqi_extzv_2_rex64): Likewise.
> ? ? ? ?(*movqi_extzv_2): Likewise.

Er, I didn't mean to remove register_operand check from 32bit
patterns... there, operand 0 can also be memory operand due to
"nonimmediate_operand" constraint.

Uros.


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