Re: [PATCH] i386: Fix up *vec_concat<mode>_0_1 [PR101007]

[Uros Bizjak <ubizjak@gmail.com>]

On Fri, Jun 11, 2021 at 10:59 AM Jakub Jelinek <jakub@redhat.com> wrote:
>
> On Fri, Apr 23, 2021 at 12:53:58PM +0800, Hongtao Liu via Gcc-patches wrote:
> > -(define_insn "*vec_concatv4si_0"
> > -  [(set (match_operand:V4SI 0 "register_operand"       "=v,x")
> > -     (vec_concat:V4SI
> > -       (match_operand:V2SI 1 "nonimmediate_operand" "vm,?!*y")
> > -       (match_operand:V2SI 2 "const0_operand"       " C,C")))]
> > +(define_insn "*vec_concat<mode>_0"
> > +  [(set (match_operand:VI124_128 0 "register_operand"       "=v,x")
> > +     (vec_concat:VI124_128
> > +       (match_operand:<ssehalfvecmode> 1 "nonimmediate_operand" "vm,?!*y")
> > +       (match_operand:<ssehalfvecmode> 2 "const0_operand"       " C,C")))]
> >    "TARGET_SSE2"
> >    "@
> >     %vmovq\t{%1, %0|%0, %1}
> > @@ -22154,6 +22157,24 @@ (define_insn "avx_vec_concat<mode>"
> >     (set_attr "prefix" "maybe_evex")
> >     (set_attr "mode" "<sseinsnmode>")])
> >
> > +(define_insn_and_split "*vec_concat<mode>_0"
> > +  [(set (match_operand:V 0 "register_operand")
> > +     (vec_select:V
> > +       (vec_concat:<ssedoublevecmode>
> > +         (match_operand:V 1 "nonimmediate_operand")
> > +         (match_operand:V 2 "const0_operand"))
> > +       (match_parallel 3 "movq_parallel"
> > +         [(match_operand 4 "const_int_operand")])))]
> > +  "ix86_pre_reload_split ()"
> > +  "#"
> > +  "&& 1"
> > +  [(set (match_dup 0)
> > +     (vec_concat:V (match_dup 1) (match_dup 5)))]
> > +{
> > +  operands[1] = gen_lowpart (<ssehalfvecmode>mode, operands[1]);
> > +  operands[5] = CONST0_RTX (<ssehalfvecmode>mode);
> > +})
>
> This regressed the following testcase with -msse -mno-sse2.
> The define_insn_and_split splits the permutation into *vec_concat<mode>_0
> or *vec_concatv2di_0 insns which both have TARGET_SSE2 in their
> conditions (for the former you can see it above), but the
> define_insn_and_split matches always when the V mode's condition do,
> which for V16QI/V8HI/V4SI/V2DI/V4SF modes is always (well, when those
> modes are valid, which is TARGET_SSE).
>
> Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux,
> ok for trunk?
>
> 2021-06-11  Jakub Jelinek  <jakub@redhat.com>
>
>         PR target/101007
>         * config/i386/sse.md (*vec_concat<mode>_0_1): Require TARGET_SSE2.
>
>         * gcc.target/i386/sse-pr101007.c: New test.

OK, even as obvious patch.

Thanks,
Uros.

> --- gcc/config/i386/sse.md.jj   2021-06-07 09:24:57.706689972 +0200
> +++ gcc/config/i386/sse.md      2021-06-10 11:14:52.407588679 +0200
> @@ -22395,7 +22395,7 @@ (define_insn_and_split "*vec_concat<mode
>             (match_operand:V 2 "const0_operand"))
>           (match_parallel 3 "movq_parallel"
>             [(match_operand 4 "const_int_operand")])))]
> -  "ix86_pre_reload_split ()"
> +  "TARGET_SSE2 && ix86_pre_reload_split ()"
>    "#"
>    "&& 1"
>    [(set (match_dup 0)
> --- gcc/testsuite/gcc.target/i386/sse-pr101007.c.jj     2021-06-10 11:41:25.818609527 +0200
> +++ gcc/testsuite/gcc.target/i386/sse-pr101007.c        2021-06-10 11:38:39.301910017 +0200
> @@ -0,0 +1,14 @@
> +/* PR target/101007 */
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -msse -mno-sse2" } */
> +
> +typedef unsigned __attribute__((__vector_size__ (8))) U;
> +typedef unsigned __attribute__((__vector_size__ (16))) V;
> +V v;
> +U *p;
> +
> +void
> +foo (void)
> +{
> +  *p = (U) __builtin_shufflevector ((V)(0 == (V){} >= 0), v, 4, 2);
> +}
>
>         Jakub
>