[Bug target/67325] New: Optimize shift (aka subreg) of load to simple load

[glisse at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67325

            Bug ID: 67325
           Summary: Optimize shift (aka subreg) of load to simple load
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: glisse at gcc dot gnu.org
  Target Milestone: ---
            Target: x86_64-linux-gnu

int f(long*l){
  return *l>>32;
}

        movq    (%rdi), %rax
        sarq    $32, %rax

While it seems to me that a single movl would do.

Classified as target (x86_64) for now, but it is more likely tree-optimization
or rtl-optimization.