Re: Is this the expected behavior?

["Mohamed Shafi" <shafitvm at gmail dot com>]

2008/7/15 Ramana Radhakrishnan <ramana.r@gmail.com>:
> <snipped parts of the last mail>
>
>>
>>   I agree with you, but what about when there are still caller save
>> register are available and there are no register restrictions for any
>> instructions? In my case i find that GCC has used only the argument
>> registers, stack pointer and callee saved registers. So out of the 16
>> available registers ony 5+1+4 registers were used, even though there
>> was 6 caller save registers were available
>
>
> Check your REG_ALLOC_ORDER macro ?

  The order is argument registers, caller save registers and finally
the callee save registers.


>
>
> cheers
> Ramana
>>
>>>
>>> HTH.
>>>
>>>
>>> cheers
>>> Ramana
>>>
>>> On Tue, Jul 15, 2008 at 7:50 AM, Mohamed Shafi <shafitvm@gmail.com> wrote:
>>>>
>>>> Hello all,
>>>>
>>>> I am not sure if this the right mailing list.
>>>>
>>>> I am involved in the porting of gcc 4.1.2 for a 16 bit target.
>>>> In some cases i noticed that callee save registers were getting
>>>> allocated in the body even though there isn't any function call. I
>>>> believe that callee save registers will be allocated only if some
>>>> variable values are required across a function call. So if there is no
>>>> function call there shouldn't be any callee save registers used in a
>>>> function body. So my question is will GCC allocate callee save
>>>> registers for function even if the function doesn't call any other
>>>> function?
>>>> Or is this a gcc bug?
>>>>
>>>> Hope my question is clear.
>>>>
>>>> Regards,
>>>> Shafi
>>>
>>>
>>>
>>> --
>>> Ramana Radhakrishnan
>>>
>>
>
>
>
> --
> Ramana Radhakrishnan
>