Hi:
  This patch is about to add a pre-reload splitter to transform
vpcmpeqd with a zero operand to vptestnmd, which could save a vpxor
instruction.

.i.e
-       vpxor   %xmm1, %xmm1, %xmm1
-       vpcmpd  $0, %zmm1, %zmm0, %k0
+       vptestnmd       %zmm0, %zmm0, %k0
        vpmovm2d zmm0, k0

Bootstrapped and regtested on x86-64_iinux-gnu{-m32,}.

gcc/ChangeLog:

        PR target/98348
        * config/i386/sse.md (*<avx512>_eq<mode>3): New pre_reload
        splitter.
        (*<avx512>_eq<mode>3): Changed from combine splitter to
        pre-reload splitter.

gcc/testsuite/ChangeLog:

        PR target/98348
        * gcc.target/i386/pr98348.c: New test.


-- 
BR,
Hongtao