Refactor Perl_get_vtbl() to a small array lookup from a large switch statement.

Provide magic_vtable_max, the number of elements in PL_magic_vtables[].

1 files changed, 2 insertions, 95 deletions

diff --git a/util.c b/util.c
index 7355d0330e..19fec65fe3 100644
--- a/util.c
+++ b/util.c
@@ -3736,103 +3736,10 @@ Perl_getenv_len(pTHX_ const char *env_elem, unsigned long *len)
 MGVTBL*
 Perl_get_vtbl(pTHX_ int vtbl_id)
 {
-    const MGVTBL* result;
     PERL_UNUSED_CONTEXT;
 
-    switch(vtbl_id) {
-    case want_vtbl_sv:
-	result = &PL_vtbl_sv;
-	break;
-    case want_vtbl_env:
-	result = &PL_vtbl_env;
-	break;
-    case want_vtbl_envelem:
-	result = &PL_vtbl_envelem;
-	break;
-#ifndef PERL_MICRO
-    case want_vtbl_sigelem:
-	result = &PL_vtbl_sigelem;
-	break;
-#endif
-    case want_vtbl_pack:
-	result = &PL_vtbl_pack;
-	break;
-    case want_vtbl_packelem:
-	result = &PL_vtbl_packelem;
-	break;
-    case want_vtbl_dbline:
-	result = &PL_vtbl_dbline;
-	break;
-    case want_vtbl_isa:
-	result = &PL_vtbl_isa;
-	break;
-    case want_vtbl_isaelem:
-	result = &PL_vtbl_isaelem;
-	break;
-    case want_vtbl_arylen:
-	result = &PL_vtbl_arylen;
-	break;
-    case want_vtbl_mglob:
-	result = &PL_vtbl_mglob;
-	break;
-    case want_vtbl_nkeys:
-	result = &PL_vtbl_nkeys;
-	break;
-    case want_vtbl_taint:
-	result = &PL_vtbl_taint;
-	break;
-    case want_vtbl_substr:
-	result = &PL_vtbl_substr;
-	break;
-    case want_vtbl_vec:
-	result = &PL_vtbl_vec;
-	break;
-    case want_vtbl_pos:
-	result = &PL_vtbl_pos;
-	break;
-    case want_vtbl_bm:
-	result = &PL_vtbl_bm;
-	break;
-    case want_vtbl_fm:
-	result = &PL_vtbl_fm;
-	break;
-    case want_vtbl_uvar:
-	result = &PL_vtbl_uvar;
-	break;
-    case want_vtbl_defelem:
-	result = &PL_vtbl_defelem;
-	break;
-    case want_vtbl_regexp:
-	result = &PL_vtbl_regexp;
-	break;
-    case want_vtbl_regdata:
-	result = &PL_vtbl_regdata;
-	break;
-    case want_vtbl_regdatum:
-	result = &PL_vtbl_regdatum;
-	break;
-#ifdef USE_LOCALE_COLLATE
-    case want_vtbl_collxfrm:
-	result = &PL_vtbl_collxfrm;
-	break;
-#endif
-    case want_vtbl_amagic:
-	result = &PL_vtbl_amagic;
-	break;
-    case want_vtbl_amagicelem:
-	result = &PL_vtbl_amagicelem;
-	break;
-    case want_vtbl_backref:
-	result = &PL_vtbl_backref;
-	break;
-    case want_vtbl_utf8:
-	result = &PL_vtbl_utf8;
-	break;
-    default:
-	result = NULL;
-	break;
-    }
-    return (MGVTBL*)result;
+    return (vtbl_id < 0 || vtbl_id >= magic_vtable_max)
+	? NULL : PL_magic_vtables + vtbl_id;
 }
 
 I32