Re: [PATCH] combine: Tweak change_zero_ext

[Christophe Lyon <christophe.lyon@linaro.org>]

On 29 November 2016 at 20:38, Uros Bizjak <ubizjak@gmail.com> wrote:
>> 2016-11-26  Segher Boessenkool  <segher@kernel.crashing.org>
>>
>> * combine.c (change_zero_ext): Also handle extends from a subreg
>> to a mode bigger than that of the operand of the subreg.
>
> This patch introduced:
>
> FAIL: gcc.target/i386/pr44578.c (internal compiler error)
>
> on i686 (or x86_64 32bit multi-lib).
>
> ./cc1 -O2 -mtune=athlon64 -m32 -quiet pr44578.c
> pr44578.c: In function ‘test’:
> pr44578.c:18:1: internal compiler error: in gen_rtx_SUBREG, at emit-rtl.c:908
>  }
>  ^
> 0x81493b gen_rtx_SUBREG(machine_mode, rtx_def*, int)
>         /home/uros/gcc-svn/trunk/gcc/emit-rtl.c:908
> 0x122609f change_zero_ext
>         /home/uros/gcc-svn/trunk/gcc/combine.c:11260
> 0x1226207 recog_for_combine
>         /home/uros/gcc-svn/trunk/gcc/combine.c:11346
> 0x1236db3 try_combine
>         /home/uros/gcc-svn/trunk/gcc/combine.c:3501
> 0x123a3e0 combine_instructions
>         /home/uros/gcc-svn/trunk/gcc/combine.c:1265
> 0x123a3e0 rest_of_handle_combine
>         /home/uros/gcc-svn/trunk/gcc/combine.c:14581
> 0x123a3e0 execute
>         /home/uros/gcc-svn/trunk/gcc/combine.c:14626
>
> Uros.

Hi,

I'm seeing a similar error on aarch64:
FAIL: gcc.target/aarch64/advsimd-intrinsics/vduph_lane.c   -O1
(internal compiler error)
with the same backtrace.

Christophe