reduce cost of SvVALID()

Now that SvVALID() no longer just checks an SV flag, but instead checks
for the existence of a certain type of magic, avoid using this more
expensive macro when its not really needed.

Also, and an extra flag test to SvVALID() to make it fail quicker.

4 files changed, 8 insertions, 7 deletions

diff --git a/gv.h b/gv.h
index 0b08b686f7..488f2cc87f 100644
--- a/gv.h
+++ b/gv.h
@@ -52,7 +52,6 @@ struct gp {
     (*({ GV * const _gvname_hek = (GV *) (gv);				\
 	   assert(isGV_with_GP(_gvname_hek));				\
 	   assert(SvTYPE(_gvname_hek) == SVt_PVGV || SvTYPE(_gvname_hek) >= SVt_PVLV); \
-	   assert(!SvVALID((SV*)_gvname_hek));				\
 	   &(GvXPVGV(_gvname_hek)->xiv_u.xivu_namehek);			\
 	 }))
 #  define GvNAME_get(gv)	({ assert(GvNAME_HEK(gv)); (char *)HEK_KEY(GvNAME_HEK(gv)); })
diff --git a/sv.c b/sv.c
index 22577084b4..7bc97f3949 100644
--- a/sv.c
+++ b/sv.c
@@ -2449,8 +2449,8 @@ Perl_sv_2iv_flags(pTHX_ SV *const sv, const I32 flags)
     }
 
     if (SvVALID(sv) || isREGEXP(sv)) {
-	/* FBMs use the space for SvIVX and SvNVX for other purposes, and use
-	   the same flag bit as SVf_IVisUV, so must not let them cache IVs.
+        /* FBMs use the space for SvIVX and SvNVX for other purposes, so
+           must not let them cache IVs.
 	   In practice they are extremely unlikely to actually get anywhere
 	   accessible by user Perl code - the only way that I'm aware of is when
 	   a constant subroutine which is used as the second argument to index.
@@ -6626,7 +6626,7 @@ Perl_sv_clear(pTHX_ SV *const orig_sv)
 		/* If we're in a stash, we don't own a reference to it.
 		 * However it does have a back reference to us, which
 		 * needs to be cleared.  */
-		if (!SvVALID(sv) && (stash = GvSTASH(sv)))
+		if ((stash = GvSTASH(sv)))
 			sv_del_backref(MUTABLE_SV(stash), sv);
 	    }
 	    /* FIXME. There are probably more unreferenced pointers to SVs
diff --git a/sv.h b/sv.h
index b97c17529d..a9aca37bf2 100644
--- a/sv.h
+++ b/sv.h
@@ -1118,7 +1118,8 @@ object type. Exposed to perl code via Internals::SvREADONLY().
 /* Does the SV have a Boyer-Moore table attached as magic?
  * 'VALID' is a poor name, but is kept for historical reasons.  */
 #define SvVALID(_svvalid) (                                  \
-               SvSMAGICAL(_svvalid)                          \
+               SvPOKp(_svvalid)                              \
+            && SvSMAGICAL(_svvalid)                          \
             && SvMAGIC(_svvalid)                             \
             && (SvMAGIC(_svvalid)->mg_type == PERL_MAGIC_bm  \
                 || mg_find(_svvalid, PERL_MAGIC_bm))         \
diff --git a/util.c b/util.c
index fb2ddec974..88f1700431 100644
--- a/util.c
+++ b/util.c
@@ -811,7 +811,8 @@ Perl_fbm_instr(pTHX_ unsigned char *big, unsigned char *bigend, SV *littlestr, U
     const unsigned char *little = (const unsigned char *)SvPV_const(littlestr,l);
     STRLEN littlelen = l;
     const I32 multiline = flags & FBMrf_MULTILINE;
-    bool tail = SvVALID(littlestr) ? cBOOL(SvTAIL(littlestr)) : FALSE;
+    bool valid = SvVALID(littlestr);
+    bool tail = valid ? cBOOL(SvTAIL(littlestr)) : FALSE;
 
     PERL_ARGS_ASSERT_FBM_INSTR;
 
@@ -945,7 +946,7 @@ Perl_fbm_instr(pTHX_ unsigned char *big, unsigned char *bigend, SV *littlestr, U
 	return NULL;
     }
 
-    if (!SvVALID(littlestr)) {
+    if (!valid) {
         /* not compiled; use Perl_ninstr() instead */
 	char * const b = ninstr((char*)big,(char*)bigend,
 			 (char*)little, (char*)little + littlelen);