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Re: Issue with delay slot scheduling?
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On 09/06/11 23:08, Mohamed Shafi wrote:
> On 6 September 2011 20:50, Jeff Law <law@redhat.com> wrote:
>>
>> On 09/06/11 08:46, Mohamed Shafi wrote:
>>> Hi,
>>>
>>> I am doing a private port in GCC 4.5.1. For the my target i see
>>> some strange behavior in delay slot scheduling. For my target
>>> the instruction in the delay slots gets executed irrespective
>>> of whether the branch is taken or not. I have generated the
>>> following code after commenting out the call to
>>> 'relax_delay_slots' in the function 'dbr_schedule'.
>> [ ... ] It looks like you have found a bug. While reorg.c is
>> supposed to work with targets that have multiple delay slots,
>> it's not something that has been extensively tested.
>>
>>>>
>>> I think REGOUT dependency of g1 between instructions 38 and 43
>>> in the delay slot is not being considered by
>>> 'try_merge_delay_insns'.
>> You're probably correct.
>>
>> Jeff
>
> How do raise a bug report, mine being a private target?
I think you provided a reasonably good description of the problem;
that should be enough given you don't have a public target. Obviously
you're in the best position to develop & test a fix. I'm willing to
review it if you do so as I know reorg.c reasonably well.
jeff
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