[Bug tree-optimization/89749] New: Very odd vector constructor

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89749

            Bug ID: 89749
           Summary: Very odd vector constructor
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hjl.tools at gmail dot com
  Target Milestone: ---

[hjl@gnu-cfl-2 pr88828]$ cat i1.i
typedef short __v8hi __attribute__ ((__vector_size__ (16)));
typedef long long int __m128i __attribute__ ((__vector_size__ (16),
__may_alias__));

__m128i
foo (__m128i __A)
{
  return (__m128i) (__v8hi) { ((__v8hi)__A)[0], ((__v8hi)__A)[1],
                              ((__v8hi)__A)[2], ((__v8hi)__A)[3],
                              ((__v8hi)__A)[4], ((__v8hi)__A)[5],
                              ((__v8hi)__A)[6], ((__v8hi)__A)[7] };
}
[hjl@gnu-cfl-2 pr88828]$ gcc -S -O2 i2.i
[hjl@gnu-cfl-2 pr88828]$ cat i2.s 
        .file   "i2.i"
        .text
        .p2align 4,,15
        .globl  foo
        .type   foo, @function
foo:
.LFB1:
        .cfi_startproc
        pextrw  $3, %xmm0, %edx
        pextrw  $2, %xmm0, %eax
        pextrw  $6, %xmm0, %ecx
        salq    $16, %rdx
        pextrw  $0, %xmm0, %esi
        orq     %rax, %rdx
        pextrw  $1, %xmm0, %eax
        salq    $16, %rdx
        orq     %rax, %rdx
        pextrw  $7, %xmm0, %eax
        salq    $16, %rax
        salq    $16, %rdx
        orq     %rcx, %rax
        pextrw  $5, %xmm0, %ecx
        orq     %rsi, %rdx
        salq    $16, %rax
        movq    %rdx, -24(%rsp)
        orq     %rcx, %rax
        pextrw  $4, %xmm0, %ecx
        salq    $16, %rax
        orq     %rcx, %rax
        movq    %rax, -16(%rsp)
        movdqa  -24(%rsp), %xmm0
        ret
        .cfi_endproc

I am expecting an empty function body.