[Bug tree-optimization/50849] New: long long right shift not vectorized

[vincenzo.innocente at cern dot ch]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50849

             Bug #: 50849
           Summary: long long  right shift not vectorized
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: vincenzo.innoce...@cern.ch


Any reason why left shift is vectorized and right shift not?

long long l1[1024], l2[1024];
void sl() {
  for (int i=0;i!=1024;++i)
    l1[i] = l2[i]<<52;
}

void rl() {
  for (int i=0;i!=1024;++i)
    l1[i] = l2[i]>>52;
}


sl():
    leaq    _l1(%rip),%rcx
    xorl    %eax,%eax
    leaq    _l2(%rip),%rdx
    movdqa    (%rdx,%rax),%xmm0
    psllq    $0x34,%xmm0
    movdqa    %xmm0,(%rcx,%rax)
    addq    $0x10,%rax
    cmpq    $0x00002000,%eax
    jne    0x00000010
    repz/ret
    nopl    (%rax)
rl():
    leaq    _l1(%rip),%rsi
    xorl    %eax,%eax
    leaq    _l2(%rip),%rcx
    movq    (%rcx,%rax),%rdx
    sarq    $0x34,%rdx
    movq    %rdx,(%rsi,%rax)
    addq    $0x08,%rax
    cmpq    $0x00002000,%eax
    jne    0x00000040
    repz/ret