[Bug target/70155] New: Use SSE for TImode load/store

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70155

            Bug ID: 70155
           Summary: Use SSE for TImode load/store
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hjl.tools at gmail dot com
                CC: ubizjak at gmail dot com, ysrumyan at gmail dot com
  Target Milestone: ---
            Target: x86-64

[hjl@gnu-mic-2 int128]$ cat x.i
extern __int128 a, b;

struct foo
{
  __int128 i;
}__attribute__ ((packed));

extern struct foo x, y;

void
foo (void)
{
  a = b;
  x = y;
}
[hjl@gnu-mic-2 int128]$ gcc -S -O2 x.i
[hjl@gnu-mic-2 int128]$ cat x.s
        .file   "x.i"
        .section        .text.unlikely,"ax",@progbits
.LCOLDB0:
        .text
.LHOTB0:
        .p2align 4,,15
        .globl  foo
        .type   foo, @function
foo:
.LFB0:
        .cfi_startproc
        movq    b(%rip), %rax
        movq    b+8(%rip), %rdx
        movq    %rax, a(%rip)
        movq    %rdx, a+8(%rip)
        movq    y(%rip), %rax
        movq    y+8(%rip), %rdx
        movq    %rax, x(%rip)
        movq    %rdx, x+8(%rip)
        ret
        .cfi_endproc
.LFE0:
        .size   foo, .-foo
        .section        .text.unlikely
.LCOLDE0:
        .text
.LHOTE0:
        .ident  "GCC: (GNU) 5.3.1 20160212 (Red Hat 5.3.1-4)"
        .section        .note.GNU-stack,"",@progbits
[hjl@gnu-mic-2 int128]$ 

We could generate

foo:
.LFB0:
        .cfi_startproc
        movdqa  b(%rip), %xmm0
        movaps  %xmm0, a(%rip)
        movdqu  y(%rip), %xmm0
        movups  %xmm0, x(%rip)
        ret
        .cfi_endproc
.LFE0: