Re: Regression [v850,mep...]: sign_extend in loop breaks zero-overhead loop generation

[Jeff Law <law@redhat.com>]

On 01/30/14 08:19, Paulo Matos wrote:
>> -----Original Message-----
>> From: Andreas Schwab [mailto:schwab@linux-m68k.org]
>> Sent: 30 January 2014 15:15
>> To: Paulo Matos
>> Cc: gcc@gcc.gnu.org
>> Subject: Re: Regression [v850,mep...]: sign_extend in loop breaks zero-overhead
>> loop generation
>>
>> Paulo Matos <pmatos@broadcom.com> writes:
>>
>>> If instead I write:
>>> void
>>> foo (short blockSize)
>>> {
>>>    short i;
>>>    unsigned short loopCount;
>>>    loopCount = (unsigned short) (blockSize + delayLength) % 8;
>>>    for (i = 0; i < loopCount; i++)
>>>        *temp_ptr++ = x ^ *temp_ptr;
>>> }
>>
>> This is still undefined.
>>
>
> OK, of course. Don't know what I am doing today.
> It's undefined because 'i' might overflow... I will get back to this. Thanks for pointing this out.
When you've got it sorted out, go ahead and file a BZ, include the 
regression markers so that it shows up in the searches most of us are 
paying the most attention to right now.

jeff