Ping?

Best regards,

Thomas

On 25/08/17 12:18, Thomas Preudhomme wrote:
> Hi,
> 
> I've now also added a couple more changes:
> 
> * size to_clear_bitmap according to maxregno to be consistent with its use
> * use directly TARGET_HARD_FLOAT instead of clear_vfpregs
> 
> 
> Original message below (ChangeLog unchanged):
> 
> Function cmse_nonsecure_entry_clear_before_return has code to deal with
> high VFP register (D16-D31) while ARMv8-M Baseline and Mainline both do
> not support more than 16 double VFP registers (D0-D15). This makes this
> security-sensitive code harder to read for not much benefit since
> libcall for cmse_nonsecure_call functions do not deal with those high
> VFP registers anyway.
> 
> This commit gets rid of this code for simplicity and fixes 2 issues in
> the same function:
> 
> - stop the first loop when reaching maxregno to avoid dealing with VFP
>    registers if targetting Thumb-1 or using -mfloat-abi=soft
> - include maxregno in that loop
> 
> ChangeLog entry is as follows:
> 
> *** gcc/ChangeLog ***
> 
> 2017-06-13  Thomas Preud'homme  <thomas.preudhomme@arm.com>
> 
>      * config/arm/arm.c (arm_option_override): Forbid ARMv8-M Security
>      Extensions with more than 16 double VFP registers.
>      (cmse_nonsecure_entry_clear_before_return): Remove second entry of
>      to_clear_mask and all code related to it.  Replace the remaining
>      entry by a sbitmap and adapt code accordingly.
> 
> Testing: Testsuite shows no regression when run for ARMv8-M Baseline and
> ARMv8-M Mainline.
> 
> Is this ok for trunk?
> 
> Best regards,
> 
> Thomas
> 
> On 23/08/17 11:56, Thomas Preudhomme wrote:
>> Ping?
>>
>> Best regards,
>>
>> Thomas
>>
>> On 17/07/17 17:25, Thomas Preudhomme wrote:
>>> My bad, found an off-by-one error in the sizing of bitmaps. Please find fixed 
>>> patch in attachment.
>>>
>>> ChangeLog entry is unchanged:
>>>
>>> *** gcc/ChangeLog ***
>>>
>>> 2017-06-13  Thomas Preud'homme  <thomas.preudhomme@arm.com>
>>>
>>>      * config/arm/arm.c (arm_option_override): Forbid ARMv8-M Security
>>>      Extensions with more than 16 double VFP registers.
>>>      (cmse_nonsecure_entry_clear_before_return): Remove second entry of
>>>      to_clear_mask and all code related to it.  Replace the remaining
>>>      entry by a sbitmap and adapt code accordingly.
>>>
>>> Best regards,
>>>
>>> Thomas
>>>
>>> On 17/07/17 09:52, Thomas Preudhomme wrote:
>>>> Ping?
>>>>
>>>> Best regards,
>>>>
>>>> Thomas
>>>>
>>>> On 12/07/17 09:59, Thomas Preudhomme wrote:
>>>>> Hi Richard,
>>>>>
>>>>> On 07/07/17 15:19, Richard Earnshaw (lists) wrote:
>>>>>>
>>>>>> Hmm, I think that's because really this is a partial conversion.  It
>>>>>> looks like doing this properly would involve moving that existing code
>>>>>> to use sbitmaps as well.  I think doing that would be better for
>>>>>> long-term maintenance perspectives, but I'm not going to insist that you
>>>>>> do it now.
>>>>>
>>>>> There's also the assert later but I've found a way to improve it slightly. 
>>>>> While switching to auto_sbitmap I also changed the code slightly to 
>>>>> allocate directly bitmaps to the right size. Since the change is probably 
>>>>> bigger than what you had in mind I'd appreciate if you can give me an OK 
>>>>> again. See updated patch in attachment. ChangeLog entry is unchanged:
>>>>>
>>>>> 2017-06-13  Thomas Preud'homme  <thomas.preudhomme@arm.com>
>>>>>
>>>>>      * config/arm/arm.c (arm_option_override): Forbid ARMv8-M Security
>>>>>      Extensions with more than 16 double VFP registers.
>>>>>      (cmse_nonsecure_entry_clear_before_return): Remove second entry of
>>>>>      to_clear_mask and all code related to it.  Replace the remaining
>>>>>      entry by a sbitmap and adapt code accordingly.
>>>>>
>>>>>>
>>>>>> As a result I'll let you take the call as to whether you keep this
>>>>>> version or go back to your earlier patch.  If you do decide to keep this
>>>>>> version, then see the comment below.
>>>>>
>>>>> Given the changes I'm more happy with how the patch looks now and making it 
>>>>> go in can be a nice incentive to change other ARMv8-M Security Extension 
>>>>> related code later on.
>>>>>
>>>>> Best regards,
>>>>>
>>>>> Thomas