[Bug target/98891] New: [11 regression] Neon logical operations not vectorized in DImode since g:cdfc0e863a03698a80c74896cbdc9f5c8c652e64

["clyon at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98891

            Bug ID: 98891
           Summary: [11 regression] Neon logical operations not vectorized
                    in DImode since
                    g:cdfc0e863a03698a80c74896cbdc9f5c8c652e64
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: clyon at gcc dot gnu.org
  Target Milestone: ---

Since g:cdfc0e863a03698a80c74896cbdc9f5c8c652e64 (r10-2761), I have noticed
that vorr/vorn is no longer vectorized in DImode.

I am compiling a modified version of
gcc/testsuite/gcc.target/arm/neon-vorns64.c with -mfloat-abi=hard
-mcpu=cortex-a9 -mfpu=auto -O3:

====================================================
#include "arm_neon.h"
#include <stdlib.h>

int64x1_t out_int64x1_t = 0;
int64x1_t arg0_int64x1_t = (int64x1_t)0xdeadbeef00000000LL;
int64x1_t arg1_int64x1_t = (int64x1_t)(~0xdead00000000beefLL);

int main (void)
{

  out_int64x1_t = vorn_s64 (arg0_int64x1_t, arg1_int64x1_t);
  if (out_int64x1_t != (int64x1_t)0xdeadbeef0000beefLL)
    abort();
  return 0;
}
====================================================

Before that commit I get:

        vldr.64 d17, [r3]       @ int
...
        vldr.64 d16, [r3, #8]   @ int
        vorn    d16, d16, d17
...

After that commit:
        ldr     lr, [r3]
        ldr     r4, [r3, #8]
        ldr     ip, [r3, #4]
        ldr     r6, [r3, #12]
        mvn     r3, lr
        orr     r0, r4, r3
...
        mvn     r3, ip
        orr     r1, r6, r3
...


Recent trunk has:
        ldrd    r2, [r1]
        ldrd    r0, [r1, #8]
        mvn     r2, r2
        mvn     r3, r3
        orr     r2, r2, r0
...
        orr     r3, r3, r1