Re: [PATCH][auto-inc-dec.c] Account for cost of move operation in FORM_PRE_ADD and FORM_POST_ADD cases

[Christophe Lyon <christophe dot lyon at linaro dot org>]

Hi Kyrill,

On 26 October 2015 at 12:52, Kyrill Tkachov <kyrylo.tkachov@arm.com> wrote:
>
> On 26/10/15 11:28, Bernd Schmidt wrote:
>>
>> On 10/26/2015 12:12 PM, Bernd Schmidt wrote:
>>>
>>>
>>> But isn't that balanced by the fact that it doesn't seem to take into
>>> account the gain of removing the inc_insn either? So I think this can't
>>> be right.
>>
>>
>> Argh, misread the code. The patch is OK with the change I suggested.
>>
>
> Thanks!
> Here's what I committed with r229344.
>
Since this commit, I've noticed:

FAIL: gcc.target/arm/lp1243022.c scan-rtl-dump subreg2 "REG_INC"
with --target arm-none-eabi --with-thumb --with-cpu=cortex-a9

as well as ICEs:
  gcc.target/aarch64/advsimd-intrinsics/vldX.c   -O2  (internal compiler error)
  gcc.target/aarch64/advsimd-intrinsics/vldX.c   -O2 -flto
-fno-use-linker-plugin -flto-partition=none  (internal compiler error)

with --target arm-none-linux-gnueabihf --with-thumb
--with-cpu=cortex-a15 --with-fpu=neon-vfpv4
and --target arm-none-linux-gnueabihf --with-thumb
--with-cpu=cortex-a57 --with-fpu=crypto-neon-fp-armv8

See for a more synthetic view:
http://people.linaro.org/~christophe.lyon/cross-validation/gcc/trunk/229344/report-build-info.html

Can you have a look?

Thanks,

Christophe.

> Kyrill
>
> 2015-10-26  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
>
>     * auto-inc-dec.c (insert_move_insn_before): Delete.
>     (attempt_change): Remember to cost the simple move in the
>     FORM_PRE_ADD and FORM_POST_ADD cases.
>
>>
>> Bernd
>>
>