[Bug middle-end/99395] New: s116 benchmark of TSVC is vectorized by clang and not by gcc

[hubicka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99395

            Bug ID: 99395
           Summary: s116 benchmark of TSVC is vectorized by clang and not
                    by gcc
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hubicka at gcc dot gnu.org
  Target Milestone: ---

s116 loop is:

real_t s116(struct args_t * func_args)
{

//    linear dependence testing

    initialise_arrays(__func__);
    gettimeofday(&func_args->t1, NULL);

    for (int nl = 0; nl < iterations*10; nl++) {
        for (int i = 0; i < LEN_1D - 5; i += 5) {
            a[i] = a[i + 1] * a[i];
            a[i + 1] = a[i + 2] * a[i + 1];
            a[i + 2] = a[i + 3] * a[i + 2];
            a[i + 3] = a[i + 4] * a[i + 3];
            a[i + 4] = a[i + 5] * a[i + 4];
        }
        dummy(a, b, c, d, e, aa, bb, cc, 0.);
    }

    gettimeofday(&func_args->t2, NULL);
    return calc_checksum(__func__);
}

and vectorized code produced by clang11 is about 2 times faster on zen3 machine

0000000000401d00 <s116>:
  401d00:       41 56                   push   %r14
  401d02:       53                      push   %rbx
  401d03:       50                      push   %rax
  401d04:       49 89 fe                mov    %rdi,%r14
  401d07:       bf 66 e1 42 00          mov    $0x42e166,%edi
  401d0c:       e8 ff 58 01 00          call   417610 <initialise_arrays>
  401d11:       31 db                   xor    %ebx,%ebx
  401d13:       4c 89 f7                mov    %r14,%rdi
  401d16:       31 f6                   xor    %esi,%esi
  401d18:       e8 43 f3 ff ff          call   401060 <gettimeofday@plt>
  401d1d:       eb 47                   jmp    401d66 <s116+0x66>
  401d1f:       90                      nop
  401d20:       bf 00 25 45 00          mov    $0x452500,%edi
  401d25:       be 00 31 43 00          mov    $0x433100,%esi
  401d2a:       ba 00 19 47 00          mov    $0x471900,%edx
  401d2f:       b9 00 0d 49 00          mov    $0x490d00,%ecx
  401d34:       41 b8 00 01 4b 00       mov    $0x4b0100,%r8d
  401d3a:       41 b9 00 f5 4c 00       mov    $0x4cf500,%r9d
  401d40:       c5 f8 57 c0             vxorps %xmm0,%xmm0,%xmm0
  401d44:       68 00 f5 54 00          push   $0x54f500
  401d49:       68 00 f5 50 00          push   $0x50f500
  401d4e:       e8 6d 3c 01 00          call   4159c0 <dummy>
  401d53:       48 83 c4 10             add    $0x10,%rsp
  401d57:       83 c3 01                add    $0x1,%ebx
  401d5a:       81 fb 40 42 0f 00       cmp    $0xf4240,%ebx
  401d60:       0f 84 9a 00 00 00       je     401e00 <s116+0x100>
  401d66:       c5 fa 10 05 92 07 05    vmovss 0x50792(%rip),%xmm0        #
452500 <a>
  401d6d:       00 
  401d6e:       31 c0                   xor    %eax,%eax
  401d70:       c5 fa 10 0c 85 04 25    vmovss 0x452504(,%rax,4),%xmm1
  401d77:       45 00 
  401d79:       c5 fa 59 c1             vmulss %xmm1,%xmm0,%xmm0
  401d7d:       c5 fa 11 04 85 00 25    vmovss %xmm0,0x452500(,%rax,4)
  401d84:       45 00 
  401d86:       c5 f8 10 04 85 08 25    vmovups 0x452508(,%rax,4),%xmm0
  401d8d:       45 00 
  401d8f:       c5 f0 c6 c8 00          vshufps $0x0,%xmm0,%xmm1,%xmm1
  401d94:       c5 f0 c6 c8 98          vshufps $0x98,%xmm0,%xmm1,%xmm1
  401d99:       c5 f8 59 c9             vmulps %xmm1,%xmm0,%xmm1
  401d9d:       c5 f8 11 0c 85 04 25    vmovups %xmm1,0x452504(,%rax,4)
  401da4:       45 00 
  401da6:       48 3d f5 7c 00 00       cmp    $0x7cf5,%rax
  401dac:       0f 87 6e ff ff ff       ja     401d20 <s116+0x20>
  401db2:       c4 e3 79 04 c0 e7       vpermilps $0xe7,%xmm0,%xmm0
  401db8:       c5 fa 10 0c 85 18 25    vmovss 0x452518(,%rax,4),%xmm1
  401dbf:       45 00 
  401dc1:       c5 fa 59 c1             vmulss %xmm1,%xmm0,%xmm0
  401dc5:       c5 fa 11 04 85 14 25    vmovss %xmm0,0x452514(,%rax,4)
  401dcc:       45 00 
  401dce:       c5 f8 10 04 85 1c 25    vmovups 0x45251c(,%rax,4),%xmm0
  401dd5:       45 00 
  401dd7:       c5 f0 c6 c8 00          vshufps $0x0,%xmm0,%xmm1,%xmm1
  401ddc:       c5 f0 c6 c8 98          vshufps $0x98,%xmm0,%xmm1,%xmm1
  401de1:       c5 f8 59 c9             vmulps %xmm1,%xmm0,%xmm1
  401de5:       c5 fa 10 04 85 28 25    vmovss 0x452528(,%rax,4),%xmm0
  401dec:       45 00 
  401dee:       c5 f8 11 0c 85 18 25    vmovups %xmm1,0x452518(,%rax,4)
  401df5:       45 00 
  401df7:       48 83 c0 0a             add    $0xa,%rax
  401dfb:       e9 70 ff ff ff          jmp    401d70 <s116+0x70>
  401e00:       49 83 c6 10             add    $0x10,%r14
  401e04:       4c 89 f7                mov    %r14,%rdi
  401e07:       31 f6                   xor    %esi,%esi
  401e09:       e8 52 f2 ff ff          call   401060 <gettimeofday@plt>
  401e0e:       bf 66 e1 42 00          mov    $0x42e166,%edi
  401e13:       48 83 c4 08             add    $0x8,%rsp
  401e17:       5b                      pop    %rbx
  401e18:       41 5e                   pop    %r14
  401e1a:       e9 e1 51 02 00          jmp    427000 <calc_checksum>
  401e1f:       90                      nop