C:\test>1064178-b.pl
                 Rate     OPdiff hash_grep OPdiffModified OPdiff_undef using_vec
OPdiff         90.9/s         --      -47%           -52%         -55%      -64%
hash_grep       170/s        87%        --           -10%         -17%      -33%
OPdiffModified  189/s       108%       11%             --          -7%      -26%
OPdiff_undef    204/s       124%       20%             8%           --      -20%
using_vec       254/s       180%       49%            35%          25%        --

##</code><code>##

C:\test>junk.pl
hash_grep:      *CMP::hash_grep
hash_key_diff:  *CMP::hash_key_diff
hash_values_diff:       *CMP::hash_values_diff
using_vec:      *CMP::using_vec

                     Rate   using_vec hash_values_diff hash_key_diff   hash_grep
using_vec         69161/s          --             -81%          -84%        -88%
hash_values_diff 363049/s        425%               --          -14%        -39%
hash_key_diff    421810/s        510%              16%            --        -29%
hash_grep        594454/s        760%              64%           41%          --

##</code><code>##

my $href = pckg_subs();
pp $href;

{
  hash_grep        => sub { "???" },
  hash_key_diff    => sub { "???" },
  hash_values_diff => sub { "???" },
  using_vec        => sub { "???" },
}