On Tue, May 17, 2022 at 9:00 AM Jakub Jelinek <ja...@redhat.com> wrote:
>
> Hi!
>
> The recent r13-458 change to introduce vec_cmpeqv1tiv1ti and
> add TARGET_SSE2 support to vec_cmpeqv2div2di works nicely for
> equality comparisons, but as the testcase shows doesn't work
> for inequality comparisons.
> For EQ if we perform comparison with twice as many half-sized elemenets,
> the result should be ~0 when both halves are ~0 only (both halves need
> to be equal for the whole to be equal), otherwise 0, so AND is the
> correct operation for it.
> But for NE, the result should be ~0 when either of the halves is ~0
> (if either half is not equal, the whole is not equal) and so the right
> operation for NE is IOR, not AND.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
>
> 2022-05-17 Jakub Jelinek <ja...@redhat.com>
>
> PR target/105613
> * config/i386/sse.md (vec_cmpeqv2div2di, vec_cmpeqv1tiv1ti): Use
> andv4si3 only for EQ, for NE use iorv4si3 instead.
>
> * gcc.c-torture/execute/pr105613.c: New test.
OK.
Thanks,
Uros.
>
> --- gcc/config/i386/sse.md.jj 2022-05-16 09:46:01.962065216 +0200
> +++ gcc/config/i386/sse.md 2022-05-16 10:48:45.698038881 +0200
> @@ -4407,7 +4407,10 @@ (define_expand "vec_cmpeqv2div2di"
> emit_insn (gen_sse2_pshufd (tmp1, ops[0], GEN_INT (0xb1)));
>
> rtx tmp2 = gen_reg_rtx (V4SImode);
> - emit_insn (gen_andv4si3 (tmp2, tmp1, ops[0]));
> + if (GET_CODE (operands[1]) == EQ)
> + emit_insn (gen_andv4si3 (tmp2, tmp1, ops[0]));
> + else
> + emit_insn (gen_iorv4si3 (tmp2, tmp1, ops[0]));
>
> emit_move_insn (operands[0], gen_lowpart (V2DImode, tmp2));
> }
> @@ -4435,7 +4438,10 @@ (define_expand "vec_cmpeqv1tiv1ti"
> emit_insn (gen_sse2_pshufd (tmp1, tmp2, GEN_INT (0x4e)));
>
> rtx tmp3 = gen_reg_rtx (V4SImode);
> - emit_insn (gen_andv4si3 (tmp3, tmp2, tmp1));
> + if (GET_CODE (operands[1]) == EQ)
> + emit_insn (gen_andv4si3 (tmp3, tmp2, tmp1));
> + else
> + emit_insn (gen_iorv4si3 (tmp3, tmp2, tmp1));
>
> emit_move_insn (operands[0], gen_lowpart (V1TImode, tmp3));
> DONE;
> --- gcc/testsuite/gcc.c-torture/execute/pr105613.c.jj 2022-05-16
> 10:42:34.286151601 +0200
> +++ gcc/testsuite/gcc.c-torture/execute/pr105613.c 2022-05-16
> 10:48:07.687562119 +0200
> @@ -0,0 +1,26 @@
> +/* PR target/105613 */
> +/* { dg-do run { target int128 } } */
> +
> +typedef unsigned __int128 __attribute__((__vector_size__ (16))) V;
> +
> +void
> +foo (V v, V *r)
> +{
> + *r = v != 0;
> +}
> +
> +int
> +main ()
> +{
> + V r;
> + foo ((V) {5}, &r);
> + if (r[0] != ~(unsigned __int128) 0)
> + __builtin_abort ();
> + foo ((V) {0x500000005ULL}, &r);
> + if (r[0] != ~(unsigned __int128) 0)
> + __builtin_abort ();
> + foo ((V) {0}, &r);
> + if (r[0] != 0)
> + __builtin_abort ();
> + return 0;
> +}
>
> Jakub
>
