[patch, libfortran] [4.7/4.8/4.9 Regression] PR38199 missed optimization: I/O performance

[Jerry DeLisle]

On 03/08/2014 04:58 AM, Steven Bosscher wrote:
> On Sat, Mar 8, 2014 at 7:38 AM, Jerry DeLisle wrote:
>> The speedup is accomplished by simply skipping over spaces without calling
>> next_read, then backing up one character and letting the existing execution path
>> proceed, preserving all the end of record code needed in next_char.
>>
>> I also remove some unneeded error checks.
> 
> Would it be enough to make them "unlikely" instead?
> 
> -      if (length < 0)
> +      if (unlikely(length < 0))
> 

Here is the revised patch leaving the error checks in place and using unlikely().

I have also added handling of kind=4 character arrays.

Regression tested on x86-64.

OK for trunk?

Jerry
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