PERL_UNUSED_CONTEXT -> remove interp context where possible

Removing context params will save machine code in the callers of these
functions, and 1 ptr of stack space. Some of these funcs are heavily used
as mg_find*. The contexts can always be readded in the future the same way
they were removed. This patch inspired by commit dc3bf40570. Also remove
PERL_UNUSED_CONTEXT when its not needed. See removal candidate rejection
rational in [perl #122106].

-Perl_hv_backreferences_p uses context in S_hv_auxinit
 commit 96a5add60f was wrong
-Perl_whichsig_sv and Perl_whichsig_pv wrongly used PERL_UNUSED_CONTEXT
 from inception in commit 84c7b88cca
-in authors opinion cast_* shouldn't be public API, no CPAN grep usage,
 can't be static and/or inline optimized since it is exported
-Perl_my_unexec move to block where it is needed, make Win32 block, context
 free, for inlining likelyhood, private api and only 2 callers in core
-Perl_my_dirfd make all blocks context free, then change proto
-Perl_bytes_cmp_utf8 wrongly used PERL_UNUSED_CONTEXT
 from inception in commit fed3ba5d6b

1 files changed, 2 insertions, 2 deletions

diff --git a/perl.c b/perl.c
index 9e0d2b5049..d9a7d1cf95 100644
--- a/perl.c
+++ b/perl.c
@@ -3531,7 +3531,6 @@ Internet, point your browser at http://www.perl.org/, the Perl Home Page.\n\n");
 void
 Perl_my_unexec(pTHX)
 {
-    PERL_UNUSED_CONTEXT;
 #ifdef UNEXEC
     SV *    prog = newSVpv(BIN_EXP, 0);
     SV *    file = newSVpv(PL_origfilename, 0);
@@ -3545,10 +3544,11 @@ Perl_my_unexec(pTHX)
     /* unexec prints msg to stderr in case of failure */
     PerlProc_exit(status);
 #else
+    PERL_UNUSED_CONTEXT;
 #  ifdef VMS
      lib$signal(SS$_DEBUG);  /* ssdef.h #included from vmsish.h */
 #  elif defined(WIN32) || defined(__CYGWIN__)
-    Perl_croak(aTHX_ "dump is not supported");
+    Perl_croak_nocontext("dump is not supported");
 #  else
     ABORT();		/* for use with undump */
 #  endif