[PATCH][ARM] Add debug dumping of cost table fields

[Kyrill Tkachov]

Ping.
https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01064.html

Thanks,
Kyrill

On 16/06/15 09:36, Kyrill Tkachov wrote:
> On 27/05/15 09:39, Andrew Pinski wrote:
>> On Wed, May 27, 2015 at 4:38 PM, Kyrill Tkachov <kyrylo.tkachov@arm.com> wrote:
>>> Ping.
>>> https://gcc.gnu.org/ml/gcc-patches/2015-05/msg00054.html
>> This and the one in AARCH64 is too noisy.  Can we have an option to
>> turn this on and default to turning them off.
> How about this? The new undocumented option can be used to turn on verbose costs dumping.
> It is off by default.
>
> Tested arm-none-eabi.
>
> Ok for trunk?
>
> Thanks,
> Kyrill
>
> 2015-06-16  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
>
>       * config/arm/arm.c (DBG_COST): New macro.
>       (arm_new_rtx_costs): Use above.
>       * config/arm/arm.opt (mdebug-rtx-costs): New option.
>
>> Thanks,
>> Andrew
>>
>>> Thanks,
>>> Kyrill
>>>
>>> On 01/05/15 15:31, Kyrill Tkachov wrote:
>>>> Hi all,
>>>>
>>>> This patch adds a macro to wrap cost field accesses into a helpful debug
>>>> dump,
>>>> saying which field is being accessed at what line and with what values.
>>>> This helped me track down cases where the costs were doing the wrong thing
>>>> by allowing me to see which path in arm_new_rtx_costs was taken.
>>>> For example, the combine log might now contain:
>>>>
>>>> Trying 2 -> 6:
>>>> Successfully matched this instruction:
>>>> (set (reg:SI 115 [ D.5348 ])
>>>>         (neg:SI (reg:SI 0 r0 [ a ])))
>>>> using extra_cost->alu.arith with cost 0 from line 10506
>>>>
>>>> which can be useful in debugging the rtx costs.
>>>>
>>>> Bootstrapped and tested on arm.
>>>>
>>>> Ok for trunk?
>>>>
>>>> Thanks,
>>>> Kyrill
>>>>
>>>>
>>>> 2015-05-01  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
>>>>
>>>>         * config/arm/arm.c (DBG_COST): New macro.
>>>>         (arm_new_rtx_costs): Use above.