[Bug target/101716] New: lea does not have a zero_extend version of it

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101716

            Bug ID: 101716
           Summary: lea does not have a zero_extend version of it
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---
            Target: x86_64-*-*

Take:
unsigned long long sample1(unsigned long long m) {
    unsigned int t = -1;
    return (m << 1) & t;
}

---- CUT ----
Currently we produce:
        lea     rax, [rdi+rdi]
        mov     eax, eax

But really we should just produce:
        lea     eax, [rdi + rdi]
        ret

Note I noticed a few other related addressing modes missing too.