Re: [PATCH GCC]Improve bound information in loop niter analysis

[Jeff Law <law@redhat.com>]

On 08/17/2015 04:01 AM, Bin.Cheng wrote:
>>
>> +      c0 = fold_convert (type, c0);
>> +      c1 = fold_convert (type, c1);
>> +
>> +      if (operand_equal_p (var, c0, 0))
>>
>> I believe if c0 is not already of type type operand-equal_p will never succeed.
> It's quite specific case targeting comparison between var and it's
> range bounds.  Given c0 is in form of "var + offc0", then the
> comparison "var + offc0 != range bounds" doesn't have any useful
> information.  Maybe useless type conversion can be handled here
> though, it might be even corner case.
My comment about useless type conversions was more about a deficiency in 
operand_equal_p's implementation.  It wasn't something I felt needed to 
be addressed in your patch.

I think using operand_equal_p is fine here.


Jeff