p6.p6

use lib </home/zoffix/CPANPRC/Benchy/lib>;
use Benchy;

augment class IO::Handle {
      method getc2(IO::Handle:D:) {
          $!decoder or die X::IO::BinaryMode.new(:trying<getc>);
          $!decoder.consume-exactly-chars2(1) || self!getc-slow-path2()
      }
      method !getc-slow-path2() {
          $!decoder.add-bytes(nqp::readfh($!PIO, buf8.new, 0x100000));
          $!decoder.consume-exactly-chars2(1) // $!decoder.consume-all-chars() || Nil
      }

      method getc3(IO::Handle:D:) {
          $!decoder or die X::IO::BinaryMode.new(:trying<getc>);
          $!decoder.consume-exactly-chars3(1) || self!getc-slow-path3()
      }
      method !getc-slow-path3() {
          $!decoder.add-bytes(nqp::readfh($!PIO, buf8.new, 0x100000));
          $!decoder.consume-exactly-chars3(1) // $!decoder.consume-all-chars() || Nil
      }
}

augment class Rakudo::Internals::VMBackedDecoder {
      method consume-exactly-chars2(int $chars --> Str) {
          my str $result = nqp::decodertakechars(self, $chars);
          nqp::isnull_s($result) ?? Str !! $result
      }
      method consume-exactly-chars3(int $chars --> Str) {
          nqp::ifnull(nqp::decodertakechars(self, $chars), Str);
      }
}

my $f = $*TMPDIR.add('foo');
$f.spurt: join "\n", 'a'..'z';

b 5_000,
  {
      my $fh = $f.open;
      $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2;
      $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2;
      $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2;
      $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2;

      $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2;
      $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2;
      $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2;
      $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2; $ = $fh.getc2;
      $fh.close;
  },
  {
      my $fh = $f.open;
      $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3;
      $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3;
      $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3;
      $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3;

      $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3;
      $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3;
      $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3;
      $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3; $ = $fh.getc3;
      $fh.close;
  },
  {
      my $fh = $f.open;
      $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;
      $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;
      $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;
      $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;

      $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;
      $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;
      $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;
      $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;       $ = $fh;
      $fh.close;
  }