rmv context from Perl_croak_no_modify and Perl_croak_xs_usage

Remove the context/pTHX from Perl_croak_no_modify and Perl_croak_xs_usage.
For croak_no_modify, it now has no parameters (and always has been
no return), and on some compilers will now be optimized to a conditional
jump. For Perl_croak_xs_usage one push asm opcode is removed at the caller.
For both funcs, their footprint in their callers (which probably are hot
code) is smaller, which means a tiny bit more room in the cache. My text
section went from 0xC1A2F to 0xC198F after apply this. Also see
http://www.nntp.perl.org/group/perl.perl5.porters/2012/11/msg195233.html .

1 files changed, 1 insertions, 1 deletions

diff --git a/pp_sys.c b/pp_sys.c
index 57679eb3dd..938aafe0f2 100644
--- a/pp_sys.c
+++ b/pp_sys.c
@@ -1100,7 +1100,7 @@ PP(pp_sselect)
 	    if (SvIsCOW(sv))
 		sv_force_normal_flags(sv, 0);
 	    if (SvREADONLY(sv) && !(SvPOK(sv) && SvCUR(sv) == 0))
-		Perl_croak_no_modify(aTHX);
+		Perl_croak_no_modify();
 	}
 	if (!SvPOK(sv)) {
 	    if (!SvPOKp(sv))