New parameters to control stringop expansion libcall strategy

[Xinliang David Li]

On Wed, Aug 7, 2013 at 5:23 PM, Joseph S. Myers <joseph@codesourcery.com> wrote:
> On Wed, 7 Aug 2013, Xinliang David Li wrote:
>
>> Index: config/i386/stringop.def
>> ===================================================================
>> --- config/i386/stringop.def  (revision 0)
>> +++ config/i386/stringop.def  (revision 0)
>> @@ -0,0 +1,42 @@
>> +/* Definitions for option handling for IA-32.
>> +   Copyright (C) 2013 Free Software Foundation, Inc.
>> +
>> +This file is part of GCC.
>> +
>> +GCC is free software; you can redistribute it and/or modify
>> +it under the terms of the GNU General Public License as published by
>> +the Free Software Foundation; either version 3, or (at your option)
>> +any later version.
>> +
>> +GCC is distributed in the hope that it will be useful,
>> +but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> +GNU General Public License for more details.
>> +
>> +Under Section 7 of GPL version 3, you are granted additional
>> +permissions described in the GCC Runtime Library Exception, version
>> +3.1, as published by the Free Software Foundation.
>
> Why the exception?  This should only be used on the host, not the target.


Sorry, I copied the boiler-plate header from i386.h -- is it wrong there too?


>
>> +  do
>> +    {
>> +      int mins, maxs;
>> +      stringop_alg alg;
>> +      char alg_name[128];
>> +      char align[16];
>> +
>> +      next_range_str = strchr (curr_range_str, ',');
>> +      if (next_range_str)
>> +        *next_range_str++ = '\0';
>> +
>> +      if (3 != sscanf (curr_range_str, "%[^:]:%d:%s", alg_name, &maxs, align))
>
> This appears to introduce buffer overruns, which is never OK - whatever
> the length of strings in the command-line arguments, you must not overflow
> fixed-width buffers, so you must specify maximum field widths for the %[]
> and %s.
>

Ok will fix.


>> +        {
>> +          warning (0, "Wrong arg %s to option %s", curr_range_str,
>> +                   is_memset ? "-mmemset_strategy=" : "-mmemcpy_strategy=");
>> +          return;
>
> Invalid option arguments should be errors, not warnings, and diagnostics
> should not start with a capital letter.  Same applies to other diagnostics
> here.
>

Ok will fix.


>> Index: config/i386/stringop.opt
>> ===================================================================
>> --- config/i386/stringop.opt  (revision 0)
>> +++ config/i386/stringop.opt  (revision 0)
>> @@ -0,0 +1,36 @@
>> +/* Definitions for option handling for IA-32.
>> +   Copyright (C) 2013 Free Software Foundation, Inc.
>> +
>> +This file is part of GCC.
>> +
>> +GCC is free software; you can redistribute it and/or modify
>> +it under the terms of the GNU General Public License as published by
>> +the Free Software Foundation; either version 3, or (at your option)
>> +any later version.
>> +
>> +GCC is distributed in the hope that it will be useful,
>> +but WITHOUT ANY WARRANTY; without even the implied warranty of
>> +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> +GNU General Public License for more details.
>> +
>> +Under Section 7 of GPL version 3, you are granted additional
>> +permissions described in the GCC Runtime Library Exception, version
>> +3.1, as published by the Free Software Foundation.
>
> Again, why the exception?

Wrong template used.

thanks,

David

>
> --
> Joseph S. Myers
> joseph@codesourcery.com