Thanks for the link. I didn't see anything in there about normalizing the source code in particular, but did try a test case with the 2018.05 version of Perl 6 with good results, in case anybody is interested:

$ cat t.p6
#!/usr/bin/env perl6

my $charé = "asdf";

if $charé {
    say "It Works!";
}

$ perl6 t.p6
It Works!
[download]

The source:

$ grep \$char t.p6 | od -c
0000000   m   y       $   c   h   a   r 303 251       =       "   a   
+s
0000020   d   f   "   ;  \n   i   f       $   c   h   a   r   e 314 20
+1
0000040       {  \n
0000043
[download]

After parsing:

$ perl6 --target=parse t.p6 | head | grep \$char | od -c
0000000   m   y       $   c   h   a   r 303 251       =       "   a   
+s
0000020   d   f   "   ;  \n   i   f       $   c   h   a   r 303 251
0000040   {  \n                   -       E   X   P   R   :       m   
+y
0000060       $   c   h   a   r 303 251       =       "   a   s   d   
+f
0000100   "  \n
0000102
[download]

Thank you for trying!

FWIW, there's nothing special about Perl 6 source code: when you run a script foo.pl, it's basically

"foo.pl".IO.slurp.EVAL

or if you're more procedurally inclined

EVAL slurp "foo.pl"

So the source code is handled exactly the same as any other source of text: assumed to be encoded in UTF-8 (by default) and thus normalized using synthetic graphemes if necessary. Also note that CRLF is such a synthetic grapheme

say "\r\n".chars; # 1