Skip the switch statement entirely if the pointer is null, rather

than the old pointless switch on '\0'. Also skip re-comparing the
first character. Faster, and generates terser object code.

p4raw-id: //depot/perl@23722

diff --git a/pp.c b/pp.c
index 2584882..03de7e4 100644 (file)
--- a/pp.c
+++ b/pp.c
@@ -564,54 +564,57 @@ PP(pp_gelem)
     gv = (GV*)POPs;
     tmpRef = Nullsv;
     sv = Nullsv;
-    switch (elem ? *elem : '\0')
-    {
-    case 'A':
-       if (strEQ(elem, "ARRAY"))
-           tmpRef = (SV*)GvAV(gv);
-       break;
-    case 'C':
-       if (strEQ(elem, "CODE"))
-           tmpRef = (SV*)GvCVu(gv);
-       break;
-    case 'F':
-       if (strEQ(elem, "FILEHANDLE")) {
-           /* finally deprecated in 5.8.0 */
-           deprecate("*glob{FILEHANDLE}");
-           tmpRef = (SV*)GvIOp(gv);
+    if (elem) {
+       /* elem will always be NUL terminated.  */
+       const char *elem2 = elem + 1;
+       switch (*elem) {
+       case 'A':
+           if (strEQ(elem2, "RRAY"))
+               tmpRef = (SV*)GvAV(gv);
+           break;
+       case 'C':
+           if (strEQ(elem2, "ODE"))
+               tmpRef = (SV*)GvCVu(gv);
+           break;
+       case 'F':
+           if (strEQ(elem2, "ILEHANDLE")) {
+               /* finally deprecated in 5.8.0 */
+               deprecate("*glob{FILEHANDLE}");
+               tmpRef = (SV*)GvIOp(gv);
+           }
+           else
+               if (strEQ(elem2, "ORMAT"))
+                   tmpRef = (SV*)GvFORM(gv);
+           break;
+       case 'G':
+           if (strEQ(elem2, "LOB"))
+               tmpRef = (SV*)gv;
+           break;
+       case 'H':
+           if (strEQ(elem2, "ASH"))
+               tmpRef = (SV*)GvHV(gv);
+           break;
+       case 'I':
+           if (*elem2 == 'O' && !elem[2])
+               tmpRef = (SV*)GvIOp(gv);
+           break;
+       case 'N':
+           if (strEQ(elem2, "AME"))
+               sv = newSVpvn(GvNAME(gv), GvNAMELEN(gv));
+           break;
+       case 'P':
+           if (strEQ(elem2, "ACKAGE")) {
+               if (HvNAME(GvSTASH(gv)))
+                   sv = newSVpv(HvNAME(GvSTASH(gv)), 0);
+               else
+                   sv = newSVpv("__ANON__",0);
+           }
+           break;
+       case 'S':
+           if (strEQ(elem2, "CALAR"))
+               tmpRef = GvSV(gv);
+           break;
        }
-       else
-       if (strEQ(elem, "FORMAT"))
-           tmpRef = (SV*)GvFORM(gv);
-       break;
-    case 'G':
-       if (strEQ(elem, "GLOB"))
-           tmpRef = (SV*)gv;
-       break;
-    case 'H':
-       if (strEQ(elem, "HASH"))
-           tmpRef = (SV*)GvHV(gv);
-       break;
-    case 'I':
-       if (strEQ(elem, "IO"))
-           tmpRef = (SV*)GvIOp(gv);
-       break;
-    case 'N':
-       if (strEQ(elem, "NAME"))
-           sv = newSVpvn(GvNAME(gv), GvNAMELEN(gv));
-       break;
-    case 'P':
-        if (strEQ(elem, "PACKAGE")) {
-            if (HvNAME(GvSTASH(gv)))
-                sv = newSVpv(HvNAME(GvSTASH(gv)), 0);
-            else
-                sv = newSVpv("__ANON__",0);
-        }
-       break;
-    case 'S':
-       if (strEQ(elem, "SCALAR"))
-           tmpRef = GvSV(gv);
-       break;
     }
     if (tmpRef)
        sv = newRV(tmpRef);