refactor av_delete

Some bad code generation/bad optimization from VC caused me to clean this
up. Dont write AvARRAY(av)[key] = NULL twice. It appears in 2 branches
just as written VC asm wise. Don't call sv_2mortal on a NULL SV*. It
works but less efficient. On VC2008 x64 -O1 this func dropped from 0x208
to 0x202 bytes of machine code after this patch.

1 files changed, 8 insertions, 8 deletions

diff --git a/av.c b/av.c
index 5ef3a557d7..c08d2c2d3f 100644
--- a/av.c
+++ b/av.c
@@ -889,23 +889,23 @@ Perl_av_delete(pTHX_ AV *av, SSize_t key, I32 flags)
 	if (!AvREAL(av) && AvREIFY(av))
 	    av_reify(av);
 	sv = AvARRAY(av)[key];
+	AvARRAY(av)[key] = NULL;
 	if (key == AvFILLp(av)) {
-	    AvARRAY(av)[key] = NULL;
 	    do {
 		AvFILLp(av)--;
 	    } while (--key >= 0 && !AvARRAY(av)[key]);
 	}
-	else
-	    AvARRAY(av)[key] = NULL;
 	if (SvSMAGICAL(av))
 	    mg_set(MUTABLE_SV(av));
     }
-    if (flags & G_DISCARD) {
-	SvREFCNT_dec(sv);
-	sv = NULL;
+    if(sv != NULL) {
+	if (flags & G_DISCARD) {
+	    SvREFCNT_dec_NN(sv);
+	    return NULL;
+	}
+	else if (AvREAL(av))
+	    sv_2mortal(sv);
     }
-    else if (AvREAL(av))
-	sv = sv_2mortal(sv);
     return sv;
 }