This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH] Fix bootstrap on ia64 with old GCC version.


On 07/03/2018 07:32 PM, Jakub Jelinek wrote:
> On Tue, Jul 03, 2018 at 07:22:19PM +0200, Martin Liška wrote:
>> In order to make GCC 4.1 happy and build current tip, we need to define
>> static constants out of a class definition.
>>
>> Ready for trunk?
>> Thanks,
>> Martin
>>
>> gcc/ChangeLog:
>>
>> 2018-07-03  Martin Liska  <mliska@suse.cz>
>>
>> 	* tree-switch-conversion.h (struct jump_table_cluster): Define
>>         constant values outside of class declaration.
> 
> That looks incorrect.  I don't see why 4.1 wouldn't allow the const static
> data members initializers inside of the class.
> 
> You just need to define those vars, and the definition (without the
> initializers) shouldn't go into the header, but to a single .c file instead
> (I know right now there is just one .c file that includes this header, but
> if we ever want to include it in more than one, it would be a problem;
> if we never want to include in more than one, the question is why we have
> the header file at all).
> 
> So IMHO keep tree-switch-conversion.h unmodified and add:
> 
> const unsigned HOST_WIDE_INT jump_table_cluster::max_ratio_for_size;
> const unsigned HOST_WIDE_INT jump_table_cluster::max_ratio_for_speed;
> 
> to tree-switch-conversion.c somewhere.

Hi.

Thanks Jakub, works for me both on x86_64 with a recent compiler and
ia64 with GCC 4.1.

I'm going to install that.

Martin

> 
>> diff --git a/gcc/tree-switch-conversion.h b/gcc/tree-switch-conversion.h
>> index 4beac785f05..8efb125aff1 100644
>> --- a/gcc/tree-switch-conversion.h
>> +++ b/gcc/tree-switch-conversion.h
>> @@ -259,12 +259,17 @@ struct jump_table_cluster: public group_cluster
>>    static bool is_enabled (void);
>>  
>>    /* Max growth ratio for code that is optimized for size.  */
>> -  static const unsigned HOST_WIDE_INT max_ratio_for_size = 3;
>> +  static const unsigned HOST_WIDE_INT max_ratio_for_size;
>>  
>>    /* Max growth ratio for code that is optimized for speed.  */
>> -  static const unsigned HOST_WIDE_INT max_ratio_for_speed = 8;
>> +  static const unsigned HOST_WIDE_INT max_ratio_for_speed;
>>  };
>>  
>> +const unsigned HOST_WIDE_INT jump_table_cluster::max_ratio_for_size = 3;
>> +
>> +const unsigned HOST_WIDE_INT jump_table_cluster::max_ratio_for_speed = 8;
>> +
>> +
>>  /* A GIMPLE switch statement can be expanded to a short sequence of bit-wise
>>  comparisons.  "switch(x)" is converted into "if ((1 << (x-MINVAL)) & CST)"
>>  where CST and MINVAL are integer constants.  This is better than a series
>>
> 
> 
> 	Jakub
> 


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]