perldelta for 3480fbaaaea8

[perl5.git] / pp_hot.c

diff --git a/pp_hot.c b/pp_hot.c
index 5557356..1094510 100644 (file)
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -76,7 +76,8 @@ PP(pp_null)
     return NORMAL;
 }
 
-/* This is sometimes called directly by pp_coreargs and pp_grepstart. */
+/* This is sometimes called directly by pp_coreargs, pp_grepstart and
+   amagic_call. */
 PP(pp_pushmark)
 {
     PUSHMARK(PL_stack_sp);
@@ -891,6 +892,8 @@ PP(pp_rv2av)
 {
     dSP; dTOPss;
     const I32 gimme = GIMME_V;
+    static const char an_array[] = "an ARRAY";
+    static const char a_hash[] = "a HASH";
     const bool is_pp_rv2av = PL_op->op_type == OP_RV2AV
                          || PL_op->op_type == OP_LVAVREF;
     const svtype type = is_pp_rv2av ? SVt_PVAV : SVt_PVHV;
@@ -903,7 +906,7 @@ PP(pp_rv2av)
        sv = SvRV(sv);
        if (UNLIKELY(SvTYPE(sv) != type))
            /* diag_listed_as: Not an ARRAY reference */
-           DIE(aTHX_ "Not %s reference", is_pp_rv2av ? "an ARRAY" : "a HASH");
+           DIE(aTHX_ "Not %s reference", is_pp_rv2av ? an_array : a_hash);
        else if (UNLIKELY(PL_op->op_flags & OPf_MOD
                && PL_op->op_private & OPpLVAL_INTRO))
            Perl_croak(aTHX_ "%s", PL_no_localize_ref);
@@ -912,7 +915,7 @@ PP(pp_rv2av)
            GV *gv;
        
            if (!isGV_with_GP(sv)) {
-               gv = Perl_softref2xv(aTHX_ sv, is_pp_rv2av ? "an ARRAY" : "a HASH",
+               gv = Perl_softref2xv(aTHX_ sv, is_pp_rv2av ? an_array : a_hash,
                                     type, &sp);
                if (!gv)
                    RETURN;
@@ -1552,7 +1555,7 @@ PP(pp_match)
     }
     NOT_REACHED; /* NOTREACHED */
 
-nope:
+  nope:
     if (global && !(dynpm->op_pmflags & PMf_CONTINUE)) {
         if (!mg)
             mg = mg_find_mglob(TARG);
@@ -1630,8 +1633,7 @@ Perl_do_readline(pTHX)
        if (gimme == G_SCALAR) {
            /* undef TARG, and push that undefined value */
            if (type != OP_RCATLINE) {
-               SV_CHECK_THINKFIRST_COW_DROP(TARG);
-               SvOK_off(TARG);
+               sv_setsv(TARG,NULL);
            }
            PUSHTARG;
        }
@@ -1875,14 +1877,14 @@ S_softref2xv_lite(pTHX_ SV *const sv, const char *const what,
 }
 
 
-/* handle one or more derefs and array/hash indexings, e.g.
- * $h->{foo} or $a[0]{$key}[$i] or f()->[1]
+/* Handle one or more aggregate derefs and array/hash indexings, e.g.
+ * $h->{foo}  or  $a[0]{$key}[$i]  or  f()->[1]
  *
  * op_aux points to an array of unions of UV / IV / SV* / PADOFFSET.
- * Each of these either contains an action, or an argument, such as
- * a UV to use as an array index, or a lexical var to retrieve.
- * In fact, several actions re stored per UV; we keep shifting new actions
- * of the one UV, and only reload when it becomes zero.
+ * Each of these either contains a set of actions, or an argument, such as
+ * an IV to use as an array index, or a lexical var to retrieve.
+ * Several actions re stored per UV; we keep shifting new actions off the
+ * one UV, and only reload when it becomes zero.
  */
 
 PP(pp_multideref)
@@ -2945,8 +2947,12 @@ PP(pp_leavesub)
     PERL_CONTEXT *cx;
     SV *sv;
 
-    if (CxMULTICALL(&cxstack[cxstack_ix]))
+    if (CxMULTICALL(&cxstack[cxstack_ix])) {
+        /* entry zero of a stack is always PL_sv_undef, which
+         * simplifies converting a '()' return into undef in scalar context */
+        assert(PL_stack_sp > PL_stack_base || *PL_stack_base == &PL_sv_undef);
        return 0;
+    }
 
     POPBLOCK(cx,newpm);
     cxstack_ix++; /* temporarily protect top context */
@@ -3094,7 +3100,7 @@ PP(pp_entersub)
        }
        /* should call AUTOLOAD now? */
        else {
-try_autoload:
+          try_autoload:
            if ((autogv = gv_autoload_pvn(GvSTASH(gv), GvNAME(gv), GvNAMELEN(gv),
                                   GvNAMEUTF8(gv) ? SVf_UTF8 : 0)))
            {
@@ -3609,11 +3615,5 @@ PP(pp_method_redir_super)
 }
 
 /*
- * Local variables:
- * c-indentation-style: bsd
- * c-basic-offset: 4
- * indent-tabs-mode: nil
- * End:
- *
  * ex: set ts=8 sts=4 sw=4 et:
  */