[PATCH] Add a new pattern in 4-insn combine

[HAO CHEN GUI]

Segher,

     Gentle ping this:

https://gcc.gnu.org/pipermail/gcc-patches/2020-November/560573.html

On 30/11/2020 上午 11:08, HAO CHEN GUI wrote:
> Hi,
>
>   This patch adds a new pattern(combine 4 insns to 3 insns) in 4-insn 
> combine. In the patch, newpat is split twice. The newpat, newi2pat and 
> newi1pat replace i3, i2 and i1 respectively. The 4 to 3 combine is 
> done at the end where all former attempts fail. In 4 insn combine 
> pre-check, the zero and sign extend are added as the patch is for the 
> issue 1 listed in pr65010.
>
>   The attachments are the patch diff file and change log file.
>
>   Bootstrapped and tested on powerpc64le, ARM and x86 with no 
> regressions. Is this okay for trunk? Any recommendations? Thanks a lot.
>