X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=pp.c;h=9cedc3fe47cccca88f1dd5e313601a666124a686;hb=ea0c2dbd5f5ac6845ecc7ec6696415bf8e27bd52;hp=bdbe010f3edb721de3f6aed2d3789bca4c33c8f9;hpb=d30e492cced9a7022652176a253f8f900679d9b0;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/pp.c b/pp.c
old mode 100644
new mode 100755
index bdbe010..9cedc3f
--- a/pp.c
+++ b/pp.c
@@ -3912,7 +3912,17 @@ PP(pp_aslice)
 
     if (SvTYPE(av) == SVt_PVAV) {
 	const I32 arybase = CopARYBASE_get(PL_curcop);
-	if (lval && PL_op->op_private & OPpLVAL_INTRO) {
+	const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
+	bool can_preserve = FALSE;
+
+	if (localizing) {
+	    MAGIC *mg;
+	    HV *stash;
+
+	    can_preserve = SvCANEXISTDELETE(av);
+	}
+
+	if (lval && localizing) {
 	    register SV **svp;
 	    I32 max = -1;
 	    for (svp = MARK + 1; svp <= SP; svp++) {
@@ -3923,18 +3933,32 @@ PP(pp_aslice)
 	    if (max > AvMAX(av))
 		av_extend(av, max);
 	}
+
 	while (++MARK <= SP) {
 	    register SV **svp;
 	    I32 elem = SvIV(*MARK);
+	    bool preeminent = TRUE;
 
 	    if (elem > 0)
 		elem -= arybase;
+	    if (localizing && can_preserve) {
+		/* If we can determine whether the element exist,
+		 * Try to preserve the existenceness of a tied array
+		 * element by using EXISTS and DELETE if possible.
+		 * Fallback to FETCH and STORE otherwise. */
+		preeminent = av_exists(av, elem);
+	    }
+
 	    svp = av_fetch(av, elem, lval);
 	    if (lval) {
 		if (!svp || *svp == &PL_sv_undef)
 		    DIE(aTHX_ PL_no_aelem, elem);
-		if (PL_op->op_private & OPpLVAL_INTRO)
-		    save_aelem(av, elem, svp);
+		if (localizing) {
+		    if (preeminent)
+			save_aelem(av, elem, svp);
+		    else
+			SAVEADELETE(av, elem);
+		}
 	    }
 	    *MARK = svp ? *svp : &PL_sv_undef;
 	}
@@ -5038,9 +5062,9 @@ PP(pp_lock)
     dSP;
     dTOPss;
     SV *retsv = sv;
+    assert(SvTYPE(retsv) != SVt_PVCV);
     SvLOCK(sv);
-    if (SvTYPE(retsv) == SVt_PVAV || SvTYPE(retsv) == SVt_PVHV
-	|| SvTYPE(retsv) == SVt_PVCV) {
+    if (SvTYPE(retsv) == SVt_PVAV || SvTYPE(retsv) == SVt_PVHV) {
 	retsv = refto(retsv);
     }
     SETs(retsv);