X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=p5sagit%2FDevel-Size.git;a=blobdiff_plain;f=Size.xs;h=9dd4f0df1eb7bc1cb7410ee2d3180998aed55138;hp=45a23a43a8bc7ab7cd689a6d9a65bd03077fa283;hb=fd495cc6d914df3af995a850cc8dd2561d4331b5;hpb=7089796d3c88758e1be965bbdbf35056e4196ad1

diff --git a/Size.xs b/Size.xs
index 45a23a4..9dd4f0d 100644
--- a/Size.xs
+++ b/Size.xs
@@ -1,8 +1,28 @@
+/* -*- mode: C -*- */
+
+#define PERL_NO_GET_CONTEXT
+
 #include "EXTERN.h"
 #include "perl.h"
 #include "XSUB.h"
 #include "ppport.h"
 
+/* Not yet in ppport.h */
+#ifndef CvISXSUB
+#  define CvISXSUB(cv)  (CvXSUB(cv) ? TRUE : FALSE)
+#endif
+#ifndef SvRV_const
+#  define SvRV_const(rv) SvRV(rv)
+#endif
+#ifndef SvOOK_offset
+#  define SvOOK_offset(sv, len) STMT_START { len = SvIVX(sv); } STMT_END
+#endif
+
+#if PERL_VERSION < 6
+#  define PL_opargs opargs
+#  define PL_op_name op_name
+#endif
+
 #ifdef _MSC_VER 
 /* "structured exception" handling is a Microsoft extension to C and C++.
    It's *not* C++ exception handling - C++ exception handling can't capture
@@ -20,27 +40,37 @@
 # define __attribute__(x)
 #endif
 
-static int regex_whine;
-static int fm_whine;
-static int dangle_whine = 0;
-
 #if 0 && defined(DEBUGGING)
 #define dbg_printf(x) printf x
 #else
 #define dbg_printf(x)
 #endif
 
-#define TAG //printf( "# %s(%d)\n", __FILE__, __LINE__ )
+#define TAG /* printf( "# %s(%d)\n", __FILE__, __LINE__ ) */
 #define carp puts
 
-#define ALIGN_BITS  ( sizeof(void*) >> 1 )
-#define BIT_BITS    3
-#define BYTE_BITS   14
-#define SLOT_BITS   ( sizeof( void*) * 8 ) - ( ALIGN_BITS + BIT_BITS + BYTE_BITS )
-#define BYTES_PER_SLOT  1 << BYTE_BITS
-#define TRACKING_SLOTS  8192 // max. 8192 for 4GB/32-bit machine
-
-typedef char* TRACKING[ TRACKING_SLOTS ];
+/* The idea is to have a tree structure to store 1 bit per possible pointer
+   address. The lowest 16 bits are stored in a block of 8092 bytes.
+   The blocks are in a 256-way tree, indexed by the reset of the pointer.
+   This can cope with 32 and 64 bit pointers, and any address space layout,
+   without excessive memory needs. The assumption is that your CPU cache
+   works :-) (And that we're not going to bust it)  */
+
+#define BYTE_BITS    3
+#define LEAF_BITS   (16 - BYTE_BITS)
+#define LEAF_MASK   0x1FFF
+
+struct state {
+    UV total_size;
+    bool regex_whine;
+    bool fm_whine;
+    bool dangle_whine;
+    bool go_yell;
+    /* My hunch (not measured) is that for most architectures pointers will
+       start with 0 bits, hence the start of this array will be hot, and the
+       end unused. So put the flags next to the hot end.  */
+    void *tracking[256];
+};
 
 /* 
     Checks to see if thing is in the bitstring. 
@@ -48,45 +78,113 @@ typedef char* TRACKING[ TRACKING_SLOTS ];
     notes thing in the segmented bitstring.
  */
 static bool
-check_new(TRACKING *tv, const void *const p) {
-    unsigned long slot =  (unsigned long)p >> (SLOT_BITS + BIT_BITS + ALIGN_BITS);
-    unsigned int  byte = ((unsigned long)p >> (ALIGN_BITS + BIT_BITS)) & 0x00003fffU;
-    unsigned int  bit  = ((unsigned long)p >> ALIGN_BITS) & 0x00000007U;
-    unsigned int  nop  =  (unsigned long)p & 0x3U;
-    
-    assert(tv);
+check_new(struct state *st, const void *const p) {
+    unsigned int bits = 8 * sizeof(void*);
+    const size_t raw_p = PTR2nat(p);
+    /* This effectively rotates the value right by the number of low always-0
+       bits in an aligned pointer. The assmption is that most (if not all)
+       pointers are aligned, and these will be in the same chain of nodes
+       (and hence hot in the cache) but we can still deal with any unaligned
+       pointers.  */
+    const size_t cooked_p
+	= (raw_p >> ALIGN_BITS) | (raw_p << (bits - ALIGN_BITS));
+    const U8 this_bit = 1 << (cooked_p & 0x7);
+    U8 **leaf_p;
+    U8 *leaf;
+    unsigned int i;
+    void **tv_p = (void **) (st->tracking);
+
     if (NULL == p) return FALSE;
     TRY_TO_CATCH_SEGV { 
         const char c = *(const char *)p;
     }
     CAUGHT_EXCEPTION {
-        if( dangle_whine ) 
+        if (st->dangle_whine) 
             warn( "Devel::Size: Encountered invalid pointer: %p\n", p );
         return FALSE;
     }
-    dbg_printf((
-        "address: %p slot: %p byte: %4x bit: %4x nop:%x\n",
-        p, slot, byte, bit, nop
-    ));
-    TAG;    
-    if( slot >= TRACKING_SLOTS ) {
-        die( "Devel::Size: Please rebuild D::S with TRACKING_SLOTS > %u\n", slot );
-    }
     TAG;    
-    if( (*tv)[ slot ] == NULL ) {
-        Newz( 0xfc0ff, (*tv)[ slot ], BYTES_PER_SLOT, char );
-    }
-    TAG;    
-    if( (*tv)[ slot ][ byte ] & ( 1 << bit ) ) {
-        return FALSE;
-    }
-    TAG;    
-    (*tv)[ slot ][ byte ] |= ( 1 << bit );
+
+    bits -= 8;
+    /* bits now 24 (32 bit pointers) or 56 (64 bit pointers) */
+
+    /* First level is always present.  */
+    do {
+	i = (unsigned int)((cooked_p >> bits) & 0xFF);
+	if (!tv_p[i])
+	    Newxz(tv_p[i], 256, void *);
+	tv_p = (void **)(tv_p[i]);
+	bits -= 8;
+    } while (bits > LEAF_BITS + BYTE_BITS);
+    /* bits now 16 always */
+#if !defined(MULTIPLICITY) || PERL_VERSION > 8 || (PERL_VERSION == 8 && PERL_SUBVERSION > 8)
+    /* 5.8.8 and early have an assert() macro that uses Perl_croak, hence needs
+       a my_perl under multiplicity  */
+    assert(bits == 16);
+#endif
+    leaf_p = (U8 **)tv_p;
+    i = (unsigned int)((cooked_p >> bits) & 0xFF);
+    if (!leaf_p[i])
+	Newxz(leaf_p[i], 1 << LEAF_BITS, U8);
+    leaf = leaf_p[i];
+
     TAG;    
+
+    i = (unsigned int)((cooked_p >> BYTE_BITS) & LEAF_MASK);
+
+    if(leaf[i] & this_bit)
+	return FALSE;
+
+    leaf[i] |= this_bit;
     return TRUE;
 }
 
-UV thing_size(const SV *const, TRACKING *);
+static void
+free_tracking_at(void **tv, int level)
+{
+    int i = 255;
+
+    if (--level) {
+	/* Nodes */
+	do {
+	    if (tv[i]) {
+		free_tracking_at((void **) tv[i], level);
+		Safefree(tv[i]);
+	    }
+	} while (i--);
+    } else {
+	/* Leaves */
+	do {
+	    if (tv[i])
+		Safefree(tv[i]);
+	} while (i--);
+    }
+}
+
+static void
+free_state(struct state *st)
+{
+    const int top_level = (sizeof(void *) * 8 - LEAF_BITS - BYTE_BITS) / 8;
+    free_tracking_at((void **)st->tracking, top_level);
+    Safefree(st);
+}
+
+/* For now, this is somewhat a compatibility bodge until the plan comes
+   together for fine grained recursion control. total_size() would recurse into
+   hash and array members, whereas sv_size() would not. However, sv_size() is
+   called with CvSTASH() of a CV, which means that if it (also) starts to
+   recurse fully, then the size of any CV now becomes the size of the entire
+   symbol table reachable from it, and potentially the entire symbol table, if
+   any subroutine makes a reference to a global (such as %SIG). The historical
+   implementation of total_size() didn't report "everything", and changing the
+   only available size to "everything" doesn't feel at all useful.  */
+
+#define NO_RECURSION 0
+#define SOME_RECURSION 1
+#define TOTAL_SIZE_RECURSION 2
+
+static void sv_size(pTHX_ struct state *, const SV *const, const int recurse);
+
 typedef enum {
     OPc_NULL,   /* 0 */
     OPc_BASEOP, /* 1 */
@@ -100,6 +198,13 @@ typedef enum {
     OPc_PVOP,   /* 9 */
     OPc_LOOP,   /* 10 */
     OPc_COP /* 11 */
+#ifdef OA_CONDOP
+    , OPc_CONDOP /* 12 */
+#endif
+#ifdef OA_GVOP
+    , OPc_GVOP /* 13 */
+#endif
+
 } opclass;
 
 static opclass
@@ -145,9 +250,17 @@ cc_opclass(const OP * const o)
         case OA_SVOP: TAG;
         return OPc_SVOP;
 
+#ifdef OA_PADOP
         case OA_PADOP: TAG;
         return OPc_PADOP;
+#endif
+
+#ifdef OA_GVOP
+        case OA_GVOP: TAG;
+        return OPc_GVOP;
+#endif
 
+#ifdef OA_PVOP_OR_SVOP
         case OA_PVOP_OR_SVOP: TAG;
             /*
              * Character translations (tr///) are usually a PVOP, keeping a 
@@ -158,6 +271,7 @@ cc_opclass(const OP * const o)
              */
         return (o->op_private & (OPpTRANS_TO_UTF|OPpTRANS_FROM_UTF))
             ? OPc_SVOP : OPc_PVOP;
+#endif
 
         case OA_LOOP: TAG;
         return OPc_LOOP;
@@ -207,6 +321,11 @@ cc_opclass(const OP * const o)
             return OPc_BASEOP;
         else
             return OPc_PVOP;
+
+#ifdef OA_CONDOP
+        case OA_CONDOP: TAG;
+	    return OPc_CONDOP;
+#endif
         }
         warn("Devel::Size: Can't determine class of operator %s, assuming BASEOP\n",
          PL_op_name[o->op_type]);
@@ -215,184 +334,166 @@ cc_opclass(const OP * const o)
     return OPc_BASEOP;
 }
 
-
-#if !defined(NV)
-#define NV double
-#endif
-
-static int go_yell = 1;
-
 /* Figure out how much magic is attached to the SV and return the
    size */
-IV magic_size(const SV * const thing, TRACKING *tv) {
-  IV total_size = 0;
-  MAGIC *magic_pointer;
-
-  /* Is there any? */
-  if (!SvMAGIC(thing)) {
-    /* No, bail */
-    return 0;
-  }
+static void
+magic_size(pTHX_ const SV * const thing, struct state *st) {
+  MAGIC *magic_pointer = SvMAGIC(thing);
 
-  /* Get the base magic pointer */
-  magic_pointer = SvMAGIC(thing);
+  /* Have we seen the magic pointer?  (NULL has always been seen before)  */
+  while (check_new(st, magic_pointer)) {
+    st->total_size += sizeof(MAGIC);
+    /* magic vtables aren't freed when magic is freed, so don't count them.
+       (They are static structures. Anything that assumes otherwise is buggy.)
+    */
 
-  /* Have we seen the magic pointer? */
-  while (magic_pointer && check_new(tv, magic_pointer)) {
-    total_size += sizeof(MAGIC);
 
     TRY_TO_CATCH_SEGV {
-        /* Have we seen the magic vtable? */
-        if (magic_pointer->mg_virtual &&
-        check_new(tv, magic_pointer->mg_virtual)) {
-          total_size += sizeof(MGVTBL);
-        }
+	sv_size(aTHX_ st, magic_pointer->mg_obj, TOTAL_SIZE_RECURSION);
+	if (magic_pointer->mg_len == HEf_SVKEY) {
+	    sv_size(aTHX_ st, (SV *)magic_pointer->mg_ptr, TOTAL_SIZE_RECURSION);
+	}
+#if defined(PERL_MAGIC_utf8) && defined (PERL_MAGIC_UTF8_CACHESIZE)
+	else if (magic_pointer->mg_type == PERL_MAGIC_utf8) {
+	    if (check_new(st, magic_pointer->mg_ptr)) {
+		st->total_size += PERL_MAGIC_UTF8_CACHESIZE * 2 * sizeof(STRLEN);
+	    }
+	}
+#endif
+	else if (magic_pointer->mg_len > 0) {
+	    if (check_new(st, magic_pointer->mg_ptr)) {
+		st->total_size += magic_pointer->mg_len;
+	    }
+	}
 
-        /* Get the next in the chain */ // ?try
+        /* Get the next in the chain */
         magic_pointer = magic_pointer->mg_moremagic;
     }
     CAUGHT_EXCEPTION { 
-        if( dangle_whine ) 
+        if (st->dangle_whine) 
             warn( "Devel::Size: Encountered bad magic at: %p\n", magic_pointer );
     }
   }
-  return total_size;
 }
 
-UV regex_size(const REGEXP * const baseregex, TRACKING *tv) {
-  UV total_size = 0;
+static void
+check_new_and_strlen(struct state *st, const char *const p) {
+    if(check_new(st, p))
+	st->total_size += 1 + strlen(p);
+}
 
-  total_size += sizeof(REGEXP);
+static void
+regex_size(const REGEXP * const baseregex, struct state *st) {
+    if(!check_new(st, baseregex))
+	return;
+  st->total_size += sizeof(REGEXP);
 #if (PERL_VERSION < 11)     
   /* Note the size of the paren offset thing */
-  total_size += sizeof(I32) * baseregex->nparens * 2;
-  total_size += strlen(baseregex->precomp);
+  st->total_size += sizeof(I32) * baseregex->nparens * 2;
+  st->total_size += strlen(baseregex->precomp);
 #else
-  total_size += sizeof(struct regexp);
-  total_size += sizeof(I32) * SvANY(baseregex)->nparens * 2;
-  /*total_size += strlen(SvANY(baseregex)->subbeg);*/
+  st->total_size += sizeof(struct regexp);
+  st->total_size += sizeof(I32) * SvANY(baseregex)->nparens * 2;
+  /*st->total_size += strlen(SvANY(baseregex)->subbeg);*/
 #endif
-  if (go_yell && !regex_whine) {
+  if (st->go_yell && !st->regex_whine) {
     carp("Devel::Size: Calculated sizes for compiled regexes are incompatible, and probably always will be");
-    regex_whine = 1;
+    st->regex_whine = 1;
   }
-
-  return total_size;
 }
 
-UV op_size(const OP * const baseop, TRACKING *tv) {
-  UV total_size = 0;
-  TRY_TO_CATCH_SEGV {
-      TAG;
-      if (check_new(tv, baseop->op_next)) {
-           total_size += op_size(baseop->op_next, tv);
-      }
-      TAG;
-      switch (cc_opclass(baseop)) {
-      case OPc_BASEOP: TAG;
-        total_size += sizeof(struct op);
-        TAG;break;
-      case OPc_UNOP: TAG;
-        total_size += sizeof(struct unop);
-        if (check_new(tv, cUNOPx(baseop)->op_first)) {
-          total_size += op_size(cUNOPx(baseop)->op_first, tv);
-        }
-        TAG;break;
-      case OPc_BINOP: TAG;
-        total_size += sizeof(struct binop);
-        if (check_new(tv, cBINOPx(baseop)->op_first)) {
-          total_size += op_size(cBINOPx(baseop)->op_first, tv);
-        }  
-        if (check_new(tv, cBINOPx(baseop)->op_last)) {
-          total_size += op_size(cBINOPx(baseop)->op_last, tv);
-        }
-        TAG;break;
-      case OPc_LOGOP: TAG;
-        total_size += sizeof(struct logop);
-        if (check_new(tv, cLOGOPx(baseop)->op_first)) {
-          total_size += op_size(cBINOPx(baseop)->op_first, tv);
-        }  
-        if (check_new(tv, cLOGOPx(baseop)->op_other)) {
-          total_size += op_size(cLOGOPx(baseop)->op_other, tv);
-        }
-        TAG;break;
-      case OPc_LISTOP: TAG;
-        total_size += sizeof(struct listop);
-        if (check_new(tv, cLISTOPx(baseop)->op_first)) {
-          total_size += op_size(cLISTOPx(baseop)->op_first, tv);
-        }  
-        if (check_new(tv, cLISTOPx(baseop)->op_last)) {
-          total_size += op_size(cLISTOPx(baseop)->op_last, tv);
-        }
-        TAG;break;
-      case OPc_PMOP: TAG;
-        total_size += sizeof(struct pmop);
-        if (check_new(tv, cPMOPx(baseop)->op_first)) {
-          total_size += op_size(cPMOPx(baseop)->op_first, tv);
-        }  
-        if (check_new(tv, cPMOPx(baseop)->op_last)) {
-          total_size += op_size(cPMOPx(baseop)->op_last, tv);
-        }
+static void
+op_size(pTHX_ const OP * const baseop, struct state *st)
+{
+    TRY_TO_CATCH_SEGV {
+	TAG;
+	if(!check_new(st, baseop))
+	    return;
+	TAG;
+	op_size(aTHX_ baseop->op_next, st);
+	TAG;
+	switch (cc_opclass(baseop)) {
+	case OPc_BASEOP: TAG;
+	    st->total_size += sizeof(struct op);
+	    TAG;break;
+	case OPc_UNOP: TAG;
+	    st->total_size += sizeof(struct unop);
+	    op_size(aTHX_ ((UNOP *)baseop)->op_first, st);
+	    TAG;break;
+	case OPc_BINOP: TAG;
+	    st->total_size += sizeof(struct binop);
+	    op_size(aTHX_ ((BINOP *)baseop)->op_first, st);
+	    op_size(aTHX_ ((BINOP *)baseop)->op_last, st);
+	    TAG;break;
+	case OPc_LOGOP: TAG;
+	    st->total_size += sizeof(struct logop);
+	    op_size(aTHX_ ((BINOP *)baseop)->op_first, st);
+	    op_size(aTHX_ ((LOGOP *)baseop)->op_other, st);
+	    TAG;break;
+#ifdef OA_CONDOP
+	case OPc_CONDOP: TAG;
+	    st->total_size += sizeof(struct condop);
+	    op_size(aTHX_ ((BINOP *)baseop)->op_first, st);
+	    op_size(aTHX_ ((CONDOP *)baseop)->op_true, st);
+	    op_size(aTHX_ ((CONDOP *)baseop)->op_false, st);
+	    TAG;break;
+#endif
+	case OPc_LISTOP: TAG;
+	    st->total_size += sizeof(struct listop);
+	    op_size(aTHX_ ((LISTOP *)baseop)->op_first, st);
+	    op_size(aTHX_ ((LISTOP *)baseop)->op_last, st);
+	    TAG;break;
+	case OPc_PMOP: TAG;
+	    st->total_size += sizeof(struct pmop);
+	    op_size(aTHX_ ((PMOP *)baseop)->op_first, st);
+	    op_size(aTHX_ ((PMOP *)baseop)->op_last, st);
 #if PERL_VERSION < 9 || (PERL_VERSION == 9 && PERL_SUBVERSION < 5)
-        if (check_new(tv, cPMOPx(baseop)->op_pmreplroot)) {
-          total_size += op_size(cPMOPx(baseop)->op_pmreplroot, tv);
-        }
-        if (check_new(tv, cPMOPx(baseop)->op_pmreplstart)) {
-          total_size += op_size(cPMOPx(baseop)->op_pmreplstart, tv);
-        }
-        if (check_new(tv, cPMOPx(baseop)->op_pmnext)) {
-          total_size += op_size((OP *)cPMOPx(baseop)->op_pmnext, tv);
-        }
+	    op_size(aTHX_ ((PMOP *)baseop)->op_pmreplroot, st);
+	    op_size(aTHX_ ((PMOP *)baseop)->op_pmreplstart, st);
 #endif
-        /* This is defined away in perl 5.8.x, but it is in there for
-           5.6.x */
+	    /* This is defined away in perl 5.8.x, but it is in there for
+	       5.6.x */
 #ifdef PM_GETRE
-        if (check_new(tv, PM_GETRE((cPMOPx(baseop))))) {
-          total_size += regex_size(PM_GETRE(cPMOPx(baseop)), tv);
-        }
+	    regex_size(PM_GETRE((PMOP *)baseop), st);
 #else
-        if (check_new(tv, cPMOPx(baseop)->op_pmregexp)) {
-          total_size += regex_size(cPMOPx(baseop)->op_pmregexp, tv);
-        }
+	    regex_size(((PMOP *)baseop)->op_pmregexp, st);
 #endif
-        TAG;break;
-      case OPc_SVOP: TAG;
-        total_size += sizeof(struct pmop);
-        if (check_new(tv, cSVOPx(baseop)->op_sv)) {
-          total_size += thing_size(cSVOPx(baseop)->op_sv, tv);
-        }
-        TAG;break;
+	    TAG;break;
+	case OPc_SVOP: TAG;
+	    st->total_size += sizeof(struct pmop);
+	    if (!(baseop->op_type == OP_AELEMFAST
+		  && baseop->op_flags & OPf_SPECIAL)) {
+		/* not an OP_PADAV replacement */
+		sv_size(aTHX_ st, ((SVOP *)baseop)->op_sv, SOME_RECURSION);
+	    }
+	    TAG;break;
+#ifdef OA_PADOP
       case OPc_PADOP: TAG;
-        total_size += sizeof(struct padop);
-        TAG;break;
-      case OPc_PVOP: TAG;
-        if (check_new(tv, cPVOPx(baseop)->op_pv)) {
-          total_size += strlen(cPVOPx(baseop)->op_pv);
-        }
-      case OPc_LOOP: TAG;
-        total_size += sizeof(struct loop);
-        if (check_new(tv, cLOOPx(baseop)->op_first)) {
-          total_size += op_size(cLOOPx(baseop)->op_first, tv);
-        }  
-        if (check_new(tv, cLOOPx(baseop)->op_last)) {
-          total_size += op_size(cLOOPx(baseop)->op_last, tv);
-        }
-        if (check_new(tv, cLOOPx(baseop)->op_redoop)) {
-          total_size += op_size(cLOOPx(baseop)->op_redoop, tv);
-        }  
-        if (check_new(tv, cLOOPx(baseop)->op_nextop)) {
-          total_size += op_size(cLOOPx(baseop)->op_nextop, tv);
-        }
-        if (check_new(tv, cLOOPx(baseop)->op_lastop)) {
-          total_size += op_size(cLOOPx(baseop)->op_lastop, tv);
-        }  
-
-        TAG;break;
-      case OPc_COP: TAG;
+	  st->total_size += sizeof(struct padop);
+	  TAG;break;
+#endif
+#ifdef OA_GVOP
+      case OPc_GVOP: TAG;
+	  st->total_size += sizeof(struct gvop);
+	  sv_size(aTHX_ st, ((GVOP *)baseop)->op_gv, SOME_RECURSION);
+	  TAG;break;
+#endif
+	case OPc_PVOP: TAG;
+	    check_new_and_strlen(st, ((PVOP *)baseop)->op_pv);
+	    TAG;break;
+	case OPc_LOOP: TAG;
+	    st->total_size += sizeof(struct loop);
+	    op_size(aTHX_ ((LOOP *)baseop)->op_first, st);
+	    op_size(aTHX_ ((LOOP *)baseop)->op_last, st);
+	    op_size(aTHX_ ((LOOP *)baseop)->op_redoop, st);
+	    op_size(aTHX_ ((LOOP *)baseop)->op_nextop, st);
+	    op_size(aTHX_ ((LOOP *)baseop)->op_lastop, st);
+	    TAG;break;
+	case OPc_COP: TAG;
         {
           COP *basecop;
           basecop = (COP *)baseop;
-          total_size += sizeof(struct cop);
+          st->total_size += sizeof(struct cop);
 
           /* Change 33656 by nicholas@mouse-mill on 2008/04/07 11:29:51
           Eliminate cop_label from struct cop by storing a label as the first
@@ -402,24 +503,14 @@ UV op_size(const OP * const baseop, TRACKING *tv) {
           before 5.11 @33656, but later than 5.10, producing slightly too
           small memory sizes on these Perls. */
 #if (PERL_VERSION < 11)
-          if (check_new(tv, basecop->cop_label)) {
-        total_size += strlen(basecop->cop_label);
-          }
+          check_new_and_strlen(st, basecop->cop_label);
 #endif
 #ifdef USE_ITHREADS
-          if (check_new(tv, basecop->cop_file)) {
-        total_size += strlen(basecop->cop_file);
-          }
-          if (check_new(tv, basecop->cop_stashpv)) {
-        total_size += strlen(basecop->cop_stashpv);
-          }
+          check_new_and_strlen(st, basecop->cop_file);
+          check_new_and_strlen(st, basecop->cop_stashpv);
 #else
-          if (check_new(tv, basecop->cop_stash)) {
-        total_size += thing_size((SV *)basecop->cop_stash, tv);
-          }
-          if (check_new(tv, basecop->cop_filegv)) {
-        total_size += thing_size((SV *)basecop->cop_filegv, tv);
-          }
+	  sv_size(aTHX_ st, (SV *)basecop->cop_stash, SOME_RECURSION);
+	  sv_size(aTHX_ st, (SV *)basecop->cop_filegv, SOME_RECURSION);
 #endif
 
         }
@@ -429,149 +520,178 @@ UV op_size(const OP * const baseop, TRACKING *tv) {
       }
   }
   CAUGHT_EXCEPTION {
-      if( dangle_whine ) 
+      if (st->dangle_whine) 
           warn( "Devel::Size: Encountered dangling pointer in opcode at: %p\n", baseop );
   }
-  return total_size;
 }
 
-#if PERL_VERSION > 9 || (PERL_VERSION == 9 && PERL_SUBVERSION > 2)
-#  define NEW_HEAD_LAYOUT
+#if PERL_VERSION < 8 || PERL_SUBVERSION < 9
+#  define SVt_LAST 16
 #endif
 
-UV thing_size(const SV * const orig_thing, TRACKING *tv) {
-  const SV *thing = orig_thing;
-  UV total_size = sizeof(SV);
-
-  switch (SvTYPE(thing)) {
-    /* Is it undef? */
-  case SVt_NULL: TAG;
-    TAG;break;
-    /* Just a plain integer. This will be differently sized depending
-       on whether purify's been compiled in */
-  case SVt_IV: TAG;
-#ifndef NEW_HEAD_LAYOUT
-#  ifdef PURIFY
-    total_size += sizeof(sizeof(XPVIV));
-#  else
-    total_size += sizeof(IV);
-#  endif
-#endif
-    TAG;break;
-    /* Is it a float? Like the int, it depends on purify */
-  case SVt_NV: TAG;
 #ifdef PURIFY
-    total_size += sizeof(sizeof(XPVNV));
+#  define MAYBE_PURIFY(normal, pure) (pure)
+#  define MAYBE_OFFSET(struct_name, member) 0
 #else
-    total_size += sizeof(NV);
+#  define MAYBE_PURIFY(normal, pure) (normal)
+#  define MAYBE_OFFSET(struct_name, member) STRUCT_OFFSET(struct_name, member)
 #endif
-    TAG;break;
-#if (PERL_VERSION < 11)     
-    /* Is it a reference? */
-  case SVt_RV: TAG;
-#ifndef NEW_HEAD_LAYOUT
-    total_size += sizeof(XRV);
-#endif
-    TAG;break;
-#endif
-    /* How about a plain string? In which case we need to add in how
-       much has been allocated */
-  case SVt_PV: TAG;
-    total_size += sizeof(XPV);
-#if (PERL_VERSION < 11)
-    total_size += SvROK(thing) ? thing_size( SvRV(thing), tv) : SvLEN(thing);
-#else
-    total_size += SvLEN(thing);
-#endif
-    TAG;break;
-    /* A string with an integer part? */
-  case SVt_PVIV: TAG;
-    total_size += sizeof(XPVIV);
-#if (PERL_VERSION < 11)
-    total_size += SvROK(thing) ? thing_size( SvRV(thing), tv) : SvLEN(thing);
-#else
-    total_size += SvLEN(thing);
-#endif
-    if(SvOOK(thing)) {
-        total_size += SvIVX(thing);
-    }
-    TAG;break;
-    /* A scalar/string/reference with a float part? */
-  case SVt_PVNV: TAG;
-    total_size += sizeof(XPVNV);
-#if (PERL_VERSION < 11)
-    total_size += SvROK(thing) ? thing_size( SvRV(thing), tv) : SvLEN(thing);
-#else
-    total_size += SvLEN(thing);
-#endif
-    TAG;break;
-  case SVt_PVMG: TAG;
-    total_size += sizeof(XPVMG);
-#if (PERL_VERSION < 11)
-    total_size += SvROK(thing) ? thing_size( SvRV(thing), tv) : SvLEN(thing);
-#else
-    total_size += SvLEN(thing);
-#endif
-    total_size += magic_size(thing, tv);
-    TAG;break;
-#if PERL_VERSION <= 8
-  case SVt_PVBM: TAG;
-    total_size += sizeof(XPVBM);
-#if (PERL_VERSION < 11)
-    total_size += SvROK(thing) ? thing_size( SvRV(thing), tv) : SvLEN(thing);
+
+const U8 body_sizes[SVt_LAST] = {
+#if PERL_VERSION < 9
+     0,                                                       /* SVt_NULL */
+     MAYBE_PURIFY(sizeof(IV), sizeof(XPVIV)),                 /* SVt_IV */
+     MAYBE_PURIFY(sizeof(NV), sizeof(XPVNV)),                 /* SVt_NV */
+     sizeof(XRV),                                             /* SVt_RV */
+     sizeof(XPV),                                             /* SVt_PV */
+     sizeof(XPVIV),                                           /* SVt_PVIV */
+     sizeof(XPVNV),                                           /* SVt_PVNV */
+     sizeof(XPVMG),                                           /* SVt_PVMG */
+     sizeof(XPVBM),                                           /* SVt_PVBM */
+     sizeof(XPVLV),                                           /* SVt_PVLV */
+     sizeof(XPVAV),                                           /* SVt_PVAV */
+     sizeof(XPVHV),                                           /* SVt_PVHV */
+     sizeof(XPVCV),                                           /* SVt_PVCV */
+     sizeof(XPVGV),                                           /* SVt_PVGV */
+     sizeof(XPVFM),                                           /* SVt_PVFM */
+     sizeof(XPVIO)                                            /* SVt_PVIO */
+#elif PERL_VERSION == 10 && PERL_SUBVERSION == 0
+     0,                                                       /* SVt_NULL */
+     0,                                                       /* SVt_BIND */
+     0,                                                       /* SVt_IV */
+     MAYBE_PURIFY(sizeof(NV), sizeof(XPVNV)),                 /* SVt_NV */
+     0,                                                       /* SVt_RV */
+     MAYBE_PURIFY(sizeof(xpv_allocated), sizeof(XPV)),        /* SVt_PV */
+     MAYBE_PURIFY(sizeof(xpviv_allocated), sizeof(XPVIV)),/* SVt_PVIV */
+     sizeof(XPVNV),                                           /* SVt_PVNV */
+     sizeof(XPVMG),                                           /* SVt_PVMG */
+     sizeof(XPVGV),                                           /* SVt_PVGV */
+     sizeof(XPVLV),                                           /* SVt_PVLV */
+     MAYBE_PURIFY(sizeof(xpvav_allocated), sizeof(XPVAV)),/* SVt_PVAV */
+     MAYBE_PURIFY(sizeof(xpvhv_allocated), sizeof(XPVHV)),/* SVt_PVHV */
+     MAYBE_PURIFY(sizeof(xpvcv_allocated), sizeof(XPVCV)),/* SVt_PVCV */
+     MAYBE_PURIFY(sizeof(xpvfm_allocated), sizeof(XPVFM)),/* SVt_PVFM */
+     sizeof(XPVIO),                                           /* SVt_PVIO */
+#elif PERL_VERSION == 10 && PERL_SUBVERSION == 1
+     0,                                                       /* SVt_NULL */
+     0,                                                       /* SVt_BIND */
+     0,                                                       /* SVt_IV */
+     MAYBE_PURIFY(sizeof(NV), sizeof(XPVNV)),                 /* SVt_NV */
+     0,                                                       /* SVt_RV */
+     sizeof(XPV) - MAYBE_OFFSET(XPV, xpv_cur),                /* SVt_PV */
+     sizeof(XPVIV) - MAYBE_OFFSET(XPV, xpv_cur),              /* SVt_PVIV */
+     sizeof(XPVNV),                                           /* SVt_PVNV */
+     sizeof(XPVMG),                                           /* SVt_PVMG */
+     sizeof(XPVGV),                                           /* SVt_PVGV */
+     sizeof(XPVLV),                                           /* SVt_PVLV */
+     sizeof(XPVAV) - MAYBE_OFFSET(XPVAV, xav_fill),           /* SVt_PVAV */
+     sizeof(XPVHV) - MAYBE_OFFSET(XPVHV, xhv_fill),           /* SVt_PVHV */
+     sizeof(XPVCV) - MAYBE_OFFSET(XPVCV, xpv_cur),            /* SVt_PVCV */
+     sizeof(XPVFM) - MAYBE_OFFSET(XPVFM, xpv_cur),            /* SVt_PVFM */
+     sizeof(XPVIO)                                            /* SVt_PVIO */
+#elif PERL_VERSION < 13
+     0,                                                       /* SVt_NULL */
+     0,                                                       /* SVt_BIND */
+     0,                                                       /* SVt_IV */
+     MAYBE_PURIFY(sizeof(NV), sizeof(XPVNV)),                 /* SVt_NV */
+     sizeof(XPV) - MAYBE_OFFSET(XPV, xpv_cur),                /* SVt_PV */
+     sizeof(XPVIV) - MAYBE_OFFSET(XPV, xpv_cur),              /* SVt_PVIV */
+     sizeof(XPVNV),                                           /* SVt_PVNV */
+     sizeof(XPVMG),                                           /* SVt_PVMG */
+     sizeof(regexp) - MAYBE_OFFSET(regexp, xpv_cur),          /* SVt_REGEXP */
+     sizeof(XPVGV),                                           /* SVt_PVGV */
+     sizeof(XPVLV),                                           /* SVt_PVLV */
+     sizeof(XPVAV) - MAYBE_OFFSET(XPVAV, xav_fill),           /* SVt_PVAV */
+     sizeof(XPVHV) - MAYBE_OFFSET(XPVHV, xhv_fill),           /* SVt_PVHV */
+     sizeof(XPVCV) - MAYBE_OFFSET(XPVCV, xpv_cur),            /* SVt_PVCV */
+     sizeof(XPVFM) - MAYBE_OFFSET(XPVFM, xpv_cur),            /* SVt_PVFM */
+     sizeof(XPVIO)                                            /* SVt_PVIO */
 #else
-    total_size += SvLEN(thing);
-#endif
-    total_size += magic_size(thing, tv);
-    TAG;break;
+     0,                                                       /* SVt_NULL */
+     0,                                                       /* SVt_BIND */
+     0,                                                       /* SVt_IV */
+     MAYBE_PURIFY(sizeof(NV), sizeof(XPVNV)),                 /* SVt_NV */
+     sizeof(XPV) - MAYBE_OFFSET(XPV, xpv_cur),                /* SVt_PV */
+     sizeof(XPVIV) - MAYBE_OFFSET(XPV, xpv_cur),              /* SVt_PVIV */
+     sizeof(XPVNV) - MAYBE_OFFSET(XPV, xpv_cur),              /* SVt_PVNV */
+     sizeof(XPVMG),                                           /* SVt_PVMG */
+     sizeof(regexp),                                          /* SVt_REGEXP */
+     sizeof(XPVGV),                                           /* SVt_PVGV */
+     sizeof(XPVLV),                                           /* SVt_PVLV */
+     sizeof(XPVAV),                                           /* SVt_PVAV */
+     sizeof(XPVHV),                                           /* SVt_PVHV */
+     sizeof(XPVCV),                                           /* SVt_PVCV */
+     sizeof(XPVFM),                                           /* SVt_PVFM */
+     sizeof(XPVIO)                                            /* SVt_PVIO */
 #endif
-  case SVt_PVLV: TAG;
-    total_size += sizeof(XPVLV);
+};
+
+static void
+sv_size(pTHX_ struct state *const st, const SV * const orig_thing,
+	const int recurse) {
+  const SV *thing = orig_thing;
+  U32 type;
+
+  if(!check_new(st, thing))
+      return;
+
+  type = SvTYPE(thing);
+  if (type > SVt_LAST) {
+      warn("Devel::Size: Unknown variable type: %d encountered\n", type);
+      return;
+  }
+  st->total_size += sizeof(SV) + body_sizes[type];
+
+  if (type >= SVt_PVMG) {
+      magic_size(aTHX_ thing, st);
+  }
+
+  switch (type) {
 #if (PERL_VERSION < 11)
-    total_size += SvROK(thing) ? thing_size( SvRV(thing), tv) : SvLEN(thing);
+    /* Is it a reference? */
+  case SVt_RV: TAG;
 #else
-    total_size += SvLEN(thing);
+  case SVt_IV: TAG;
 #endif
-    total_size += magic_size(thing, tv);
+    if(recurse && SvROK(thing))
+	sv_size(aTHX_ st, SvRV_const(thing), recurse);
     TAG;break;
-    /* How much space is dedicated to the array? Not counting the
-       elements in the array, mind, just the array itself */
+
   case SVt_PVAV: TAG;
-    total_size += sizeof(XPVAV);
     /* Is there anything in the array? */
     if (AvMAX(thing) != -1) {
       /* an array with 10 slots has AvMax() set to 9 - te 2007-04-22 */
-      total_size += sizeof(SV *) * (AvMAX(thing) + 1);
-      dbg_printf(("total_size: %li AvMAX: %li av_len: $i\n", total_size, AvMAX(thing), av_len((AV*)thing)));
+      st->total_size += sizeof(SV *) * (AvMAX(thing) + 1);
+      dbg_printf(("total_size: %li AvMAX: %li av_len: $i\n", st->total_size, AvMAX(thing), av_len((AV*)thing)));
+
+      if (recurse >= TOTAL_SIZE_RECURSION) {
+	  SSize_t i = AvFILLp(thing) + 1;
+
+	  while (i--)
+	      sv_size(aTHX_ st, AvARRAY(thing)[i], recurse);
+      }
     }
     /* Add in the bits on the other side of the beginning */
 
     dbg_printf(("total_size %li, sizeof(SV *) %li, AvARRAY(thing) %li, AvALLOC(thing)%li , sizeof(ptr) %li \n", 
-    total_size, sizeof(SV*), AvARRAY(thing), AvALLOC(thing), sizeof( thing )));
+    st->total_size, sizeof(SV*), AvARRAY(thing), AvALLOC(thing), sizeof( thing )));
 
     /* under Perl 5.8.8 64bit threading, AvARRAY(thing) was a pointer while AvALLOC was 0,
        resulting in grossly overstated sized for arrays. Technically, this shouldn't happen... */
     if (AvALLOC(thing) != 0) {
-      total_size += (sizeof(SV *) * (AvARRAY(thing) - AvALLOC(thing)));
+      st->total_size += (sizeof(SV *) * (AvARRAY(thing) - AvALLOC(thing)));
       }
 #if (PERL_VERSION < 9)
     /* Is there something hanging off the arylen element?
        Post 5.9.something this is stored in magic, so will be found there,
        and Perl_av_arylen_p() takes a non-const AV*, hence compilers rightly
        complain about AvARYLEN() passing thing to it.  */
-    if (AvARYLEN(thing)) {
-      if (check_new(tv, AvARYLEN(thing))) {
-    total_size += thing_size(AvARYLEN(thing), tv);
-      }
-    }
+    sv_size(aTHX_ st, AvARYLEN(thing), recurse);
 #endif
-    total_size += magic_size(thing, tv);
     TAG;break;
   case SVt_PVHV: TAG;
-    /* First the base struct */
-    total_size += sizeof(XPVHV);
     /* Now the array of buckets */
-    total_size += (sizeof(HE *) * (HvMAX(thing) + 1));
+    st->total_size += (sizeof(HE *) * (HvMAX(thing) + 1));
     /* Now walk the bucket chain */
     if (HvARRAY(thing)) {
       HE *cur_entry;
@@ -579,132 +699,55 @@ UV thing_size(const SV * const orig_thing, TRACKING *tv) {
       for (cur_bucket = 0; cur_bucket <= HvMAX(thing); cur_bucket++) {
         cur_entry = *(HvARRAY(thing) + cur_bucket);
         while (cur_entry) {
-          total_size += sizeof(HE);
+          st->total_size += sizeof(HE);
           if (cur_entry->hent_hek) {
             /* Hash keys can be shared. Have we seen this before? */
-            if (check_new(tv, cur_entry->hent_hek)) {
-              total_size += HEK_BASESIZE + cur_entry->hent_hek->hek_len + 2;
+            if (check_new(st, cur_entry->hent_hek)) {
+              st->total_size += HEK_BASESIZE + cur_entry->hent_hek->hek_len + 2;
             }
           }
+	  if (recurse >= TOTAL_SIZE_RECURSION)
+	      sv_size(aTHX_ st, HeVAL(cur_entry), recurse);
           cur_entry = cur_entry->hent_next;
         }
       }
     }
-    total_size += magic_size(thing, tv);
     TAG;break;
-  case SVt_PVCV: TAG;
-    total_size += sizeof(XPVCV);
-    total_size += magic_size(thing, tv);
 
-    total_size += ((XPVIO *) SvANY(thing))->xpv_len;
-    if (check_new(tv, CvSTASH(thing))) {
-      total_size += thing_size((SV *)CvSTASH(thing), tv);
-    }
-    if (check_new(tv, SvSTASH(thing))) {
-      total_size += thing_size( (SV *)SvSTASH(thing), tv);
-    }
-    if (check_new(tv, CvGV(thing))) {
-      total_size += thing_size((SV *)CvGV(thing), tv);
-    }
-    if (check_new(tv, CvPADLIST(thing))) {
-      total_size += thing_size((SV *)CvPADLIST(thing), tv);
-    }
-    if (check_new(tv, CvOUTSIDE(thing))) {
-      total_size += thing_size((SV *)CvOUTSIDE(thing), tv);
-    }
-    if (check_new(tv, CvSTART(thing))) {
-      total_size += op_size(CvSTART(thing), tv);
-    }
-    if (check_new(tv, CvROOT(thing))) {
-      total_size += op_size(CvROOT(thing), tv);
-    }
 
-    TAG;break;
-  case SVt_PVGV: TAG;
-    total_size += magic_size(thing, tv);
-    total_size += sizeof(XPVGV);
-    total_size += GvNAMELEN(thing);
-#ifdef GvFILE
-    /* Is there a file? */
-    if (GvFILE(thing)) {
-      if (check_new(tv, GvFILE(thing))) {
-    total_size += strlen(GvFILE(thing));
-      }
-    }
-#endif
-    /* Is there something hanging off the glob? */
-    if (GvGP(thing)) {
-      if (check_new(tv, GvGP(thing))) {
-    total_size += sizeof(GP);
-    {
-      SV *generic_thing;
-      if ((generic_thing = (SV *)(GvGP(thing)->gp_sv))) {
-        total_size += thing_size(generic_thing, tv);
-      }
-      if ((generic_thing = (SV *)(GvGP(thing)->gp_form))) {
-        total_size += thing_size(generic_thing, tv);
-      }
-      if ((generic_thing = (SV *)(GvGP(thing)->gp_av))) {
-        total_size += thing_size(generic_thing, tv);
-      }
-      if ((generic_thing = (SV *)(GvGP(thing)->gp_hv))) {
-        total_size += thing_size(generic_thing, tv);
-      }
-      if ((generic_thing = (SV *)(GvGP(thing)->gp_egv))) {
-        total_size += thing_size(generic_thing, tv);
-      }
-      if ((generic_thing = (SV *)(GvGP(thing)->gp_cv))) {
-        total_size += thing_size(generic_thing, tv);
-      }
-    }
-      }
-    }
-    TAG;break;
   case SVt_PVFM: TAG;
-    total_size += sizeof(XPVFM);
-    total_size += magic_size(thing, tv);
-    total_size += ((XPVIO *) SvANY(thing))->xpv_len;
-    if (check_new(tv, CvPADLIST(thing))) {
-      total_size += thing_size((SV *)CvPADLIST(thing), tv);
-    }
-    if (check_new(tv, CvOUTSIDE(thing))) {
-      total_size += thing_size((SV *)CvOUTSIDE(thing), tv);
-    }
+    sv_size(aTHX_ st, (SV *)CvPADLIST(thing), SOME_RECURSION);
+    sv_size(aTHX_ st, (SV *)CvOUTSIDE(thing), recurse);
 
-    if (go_yell && !fm_whine) {
+    if (st->go_yell && !st->fm_whine) {
       carp("Devel::Size: Calculated sizes for FMs are incomplete");
-      fm_whine = 1;
+      st->fm_whine = 1;
     }
-    TAG;break;
-  case SVt_PVIO: TAG;
-    total_size += sizeof(XPVIO);
-    total_size += magic_size(thing, tv);
-    if (check_new(tv, (SvPVX_const(thing)))) {
-      total_size += ((XPVIO *) SvANY(thing))->xpv_cur;
+    goto freescalar;
+
+  case SVt_PVCV: TAG;
+    sv_size(aTHX_ st, (SV *)CvSTASH(thing), SOME_RECURSION);
+    sv_size(aTHX_ st, (SV *)SvSTASH(thing), SOME_RECURSION);
+    sv_size(aTHX_ st, (SV *)CvGV(thing), SOME_RECURSION);
+    sv_size(aTHX_ st, (SV *)CvPADLIST(thing), SOME_RECURSION);
+    sv_size(aTHX_ st, (SV *)CvOUTSIDE(thing), recurse);
+    if (CvISXSUB(thing)) {
+	sv_size(aTHX_ st, cv_const_sv((CV *)thing), recurse);
+    } else {
+	op_size(aTHX_ CvSTART(thing), st);
+	op_size(aTHX_ CvROOT(thing), st);
     }
+    goto freescalar;
+
+  case SVt_PVIO: TAG;
     /* Some embedded char pointers */
-    if (check_new(tv, ((XPVIO *) SvANY(thing))->xio_top_name)) {
-      total_size += strlen(((XPVIO *) SvANY(thing))->xio_top_name);
-    }
-    if (check_new(tv, ((XPVIO *) SvANY(thing))->xio_fmt_name)) {
-      total_size += strlen(((XPVIO *) SvANY(thing))->xio_fmt_name);
-    }
-    if (check_new(tv, ((XPVIO *) SvANY(thing))->xio_bottom_name)) {
-      total_size += strlen(((XPVIO *) SvANY(thing))->xio_bottom_name);
-    }
+    check_new_and_strlen(st, ((XPVIO *) SvANY(thing))->xio_top_name);
+    check_new_and_strlen(st, ((XPVIO *) SvANY(thing))->xio_fmt_name);
+    check_new_and_strlen(st, ((XPVIO *) SvANY(thing))->xio_bottom_name);
     /* Throw the GVs on the list to be walked if they're not-null */
-    if (((XPVIO *) SvANY(thing))->xio_top_gv) {
-      total_size += thing_size((SV *)((XPVIO *) SvANY(thing))->xio_top_gv, 
-                   tv);
-    }
-    if (((XPVIO *) SvANY(thing))->xio_bottom_gv) {
-      total_size += thing_size((SV *)((XPVIO *) SvANY(thing))->xio_bottom_gv, 
-                   tv);
-    }
-    if (((XPVIO *) SvANY(thing))->xio_fmt_gv) {
-      total_size += thing_size((SV *)((XPVIO *) SvANY(thing))->xio_fmt_gv, 
-                   tv);
-    }
+    sv_size(aTHX_ st, (SV *)((XPVIO *) SvANY(thing))->xio_top_gv, recurse);
+    sv_size(aTHX_ st, (SV *)((XPVIO *) SvANY(thing))->xio_bottom_gv, recurse);
+    sv_size(aTHX_ st, (SV *)((XPVIO *) SvANY(thing))->xio_fmt_gv, recurse);
 
     /* Only go trotting through the IO structures if they're really
        trottable. If USE_PERLIO is defined we can do this. If
@@ -713,225 +756,112 @@ UV thing_size(const SV * const orig_thing, TRACKING *tv) {
     /* Dig into xio_ifp and xio_ofp here */
     warn("Devel::Size: Can't size up perlio layers yet\n");
 #endif
+    goto freescalar;
+
+  case SVt_PVLV: TAG;
+#if (PERL_VERSION < 9)
+    goto freescalar;
+#endif
+
+  case SVt_PVGV: TAG;
+    if(isGV_with_GP(thing)) {
+	st->total_size += GvNAMELEN(thing);
+#ifdef GvFILE
+#  if !defined(USE_ITHREADS) || (PERL_VERSION > 8 || (PERL_VERSION == 8 && PERL_SUBVERSION > 8))
+	/* With itreads, before 5.8.9, this can end up pointing to freed memory
+	   if the GV was created in an eval, as GvFILE() points to CopFILE(),
+	   and the relevant COP has been freed on scope cleanup after the eval.
+	   5.8.9 adds a binary compatible fudge that catches the vast majority
+	   of cases. 5.9.something added a proper fix, by converting the GP to
+	   use a shared hash key (porperly reference counted), instead of a
+	   char * (owned by who knows? possibly no-one now) */
+	check_new_and_strlen(st, GvFILE(thing));
+#  endif
+#endif
+	/* Is there something hanging off the glob? */
+	if (check_new(st, GvGP(thing))) {
+	    st->total_size += sizeof(GP);
+	    sv_size(aTHX_ st, (SV *)(GvGP(thing)->gp_sv), recurse);
+	    sv_size(aTHX_ st, (SV *)(GvGP(thing)->gp_form), recurse);
+	    sv_size(aTHX_ st, (SV *)(GvGP(thing)->gp_av), recurse);
+	    sv_size(aTHX_ st, (SV *)(GvGP(thing)->gp_hv), recurse);
+	    sv_size(aTHX_ st, (SV *)(GvGP(thing)->gp_egv), recurse);
+	    sv_size(aTHX_ st, (SV *)(GvGP(thing)->gp_cv), recurse);
+	}
+#if (PERL_VERSION >= 9)
+	TAG; break;
+#endif
+    }
+#if PERL_VERSION <= 8
+  case SVt_PVBM: TAG;
+#endif
+  case SVt_PVMG: TAG;
+  case SVt_PVNV: TAG;
+  case SVt_PVIV: TAG;
+  case SVt_PV: TAG;
+  freescalar:
+    if(recurse && SvROK(thing))
+	sv_size(aTHX_ st, SvRV_const(thing), recurse);
+    else
+	st->total_size += SvLEN(thing);
+
+    if(SvOOK(thing)) {
+	STRLEN len;
+	SvOOK_offset(thing, len);
+	st->total_size += len;
+    }
     TAG;break;
-  default:
-    warn("Devel::Size: Unknown variable type: %d encountered\n", SvTYPE(thing) );
+
   }
-  return total_size;
+  return;
+}
+
+static struct state *
+new_state(pTHX)
+{
+    SV *warn_flag;
+    struct state *st;
+
+    Newxz(st, 1, struct state);
+    st->go_yell = TRUE;
+    if (NULL != (warn_flag = perl_get_sv("Devel::Size::warn", FALSE))) {
+	st->dangle_whine = st->go_yell = SvIV(warn_flag) ? TRUE : FALSE;
+    }
+    if (NULL != (warn_flag = perl_get_sv("Devel::Size::dangle", FALSE))) {
+	st->dangle_whine = SvIV(warn_flag) ? TRUE : FALSE;
+    }
+    check_new(st, &PL_sv_undef);
+    check_new(st, &PL_sv_no);
+    check_new(st, &PL_sv_yes);
+#if PERL_VERSION > 8 || (PERL_VERSION == 8 && PERL_SUBVERSION > 0)
+    check_new(st, &PL_sv_placeholder);
+#endif
+    return st;
 }
 
 MODULE = Devel::Size        PACKAGE = Devel::Size       
 
 PROTOTYPES: DISABLE
 
-IV
+UV
 size(orig_thing)
      SV *orig_thing
+ALIAS:
+    total_size = TOTAL_SIZE_RECURSION
 CODE:
 {
-  int i;
   SV *thing = orig_thing;
-  /* Hash to track our seen pointers */
-  //HV *tracking_hash = newHV();
-  SV *warn_flag;
-  TRACKING *tv;
-  Newz( 0xfc0ff, tv, 1, TRACKING );
-
-  /* Check warning status */
-  go_yell = 0;
-  regex_whine = 0;
-  fm_whine = 0;
-
-  if (NULL != (warn_flag = perl_get_sv("Devel::Size::warn", FALSE))) {
-    dangle_whine = go_yell = SvIV(warn_flag);
-  }
-  if (NULL != (warn_flag = perl_get_sv("Devel::Size::dangle", FALSE))) {
-    dangle_whine = SvIV(warn_flag);
-  }
+  struct state *st = new_state(aTHX);
   
   /* If they passed us a reference then dereference it. This is the
      only way we can check the sizes of arrays and hashes */
-#if (PERL_VERSION < 11)
-  if (SvOK(thing) && SvROK(thing)) {
-    thing = SvRV(thing);
-  }
-#else
   if (SvROK(thing)) {
     thing = SvRV(thing);
   }
-#endif
 
-  RETVAL = thing_size(thing, tv);
-  /* Clean up after ourselves */
-  //SvREFCNT_dec(tracking_hash);
-  for( i = 0; i < TRACKING_SLOTS; ++i ) {
-    if( (*tv)[ i ] )
-        Safefree( (*tv)[ i ] );
-  }
-  Safefree( tv );    
+  sv_size(aTHX_ st, thing, ix);
+  RETVAL = st->total_size;
+  free_state(st);
 }
 OUTPUT:
   RETVAL
-
-
-IV
-total_size(orig_thing)
-       SV *orig_thing
-CODE:
-{
-  int i;
-  SV *thing = orig_thing;
-  /* Hash to track our seen pointers */
-  //HV *tracking_hash;
-  TRACKING *tv;
-  /* Array with things we still need to do */
-  AV *pending_array;
-  IV size = 0;
-  SV *warn_flag;
-
-  /* Size starts at zero */
-  RETVAL = 0;
-
-  /* Check warning status */
-  go_yell = 0;
-  regex_whine = 0;
-  fm_whine = 0;
-
-  if (NULL != (warn_flag = perl_get_sv("Devel::Size::warn", FALSE))) {
-    dangle_whine = go_yell = SvIV(warn_flag);
-  }
-  if (NULL != (warn_flag = perl_get_sv("Devel::Size::dangle", FALSE))) {
-    dangle_whine = SvIV(warn_flag);
-  }
-
-  /* init these after the go_yell above */
-  //tracking_hash = newHV();
-  Newz( 0xfc0ff, tv, 1, TRACKING );
-  pending_array = newAV();
-
-  /* We cannot push HV/AV directly, only the RV. So deref it
-     later (see below for "*** dereference later") and adjust here for
-     the miscalculation.
-     This is the only way we can check the sizes of arrays and hashes. */
-  if (SvROK(thing)) {
-      RETVAL -= thing_size(thing, NULL);
-  } 
-
-  /* Put it on the pending array */
-  av_push(pending_array, thing);
-
-  /* Now just yank things off the end of the array until it's done */
-  while (av_len(pending_array) >= 0) {
-    thing = av_pop(pending_array);
-    /* Process it if we've not seen it */
-    if (check_new(tv, thing)) {
-      dbg_printf(("# Found type %i at %p\n", SvTYPE(thing), thing));
-      /* Is it valid? */
-      if (thing) {
-    /* Yes, it is. So let's check the type */
-    switch (SvTYPE(thing)) {
-    /* fix for bug #24846 (Does not correctly recurse into references in a PVNV-type scalar) */
-    case SVt_PVNV: TAG;
-      if (SvROK(thing))
-        {
-        av_push(pending_array, SvRV(thing));
-        } 
-      TAG;break;
-
-    /* this is the "*** dereference later" part - see above */
-#if (PERL_VERSION < 11)
-        case SVt_RV: TAG;
-#else
-        case SVt_IV: TAG;
-#endif
-             dbg_printf(("# Found RV\n"));
-          if (SvROK(thing)) {
-             dbg_printf(("# Found RV\n"));
-             av_push(pending_array, SvRV(thing));
-          }
-          TAG;break;
-
-    case SVt_PVAV: TAG;
-      {
-        AV *tempAV = (AV *)thing;
-        SV **tempSV;
-
-        dbg_printf(("# Found type AV\n"));
-        /* Quick alias to cut down on casting */
-        
-        /* Any elements? */
-        if (av_len(tempAV) != -1) {
-          IV index;
-          /* Run through them all */
-          for (index = 0; index <= av_len(tempAV); index++) {
-        /* Did we get something? */
-        if ((tempSV = av_fetch(tempAV, index, 0))) {
-          /* Was it undef? */
-          if (*tempSV != &PL_sv_undef) {
-            /* Apparently not. Save it for later */
-            av_push(pending_array, *tempSV);
-          }
-        }
-          }
-        }
-      }
-      TAG;break;
-
-    case SVt_PVHV: TAG;
-      dbg_printf(("# Found type HV\n"));
-      /* Is there anything in here? */
-      if (hv_iterinit((HV *)thing)) {
-        HE *temp_he;
-        while ((temp_he = hv_iternext((HV *)thing))) {
-          av_push(pending_array, hv_iterval((HV *)thing, temp_he));
-        }
-      }
-      TAG;break;
-     
-    case SVt_PVGV: TAG;
-      dbg_printf(("# Found type GV\n"));
-      /* Run through all the pieces and push the ones with bits */
-      if (GvSV(thing)) {
-        av_push(pending_array, (SV *)GvSV(thing));
-      }
-      if (GvFORM(thing)) {
-        av_push(pending_array, (SV *)GvFORM(thing));
-      }
-      if (GvAV(thing)) {
-        av_push(pending_array, (SV *)GvAV(thing));
-      }
-      if (GvHV(thing)) {
-        av_push(pending_array, (SV *)GvHV(thing));
-      }
-      if (GvCV(thing)) {
-        av_push(pending_array, (SV *)GvCV(thing));
-      }
-      TAG;break;
-    default:
-      TAG;break;
-    }
-      }
-      
-      size = thing_size(thing, tv);
-      RETVAL += size;
-    } else {
-    /* check_new() returned false: */
-#ifdef DEVEL_SIZE_DEBUGGING
-       if (SvOK(sv)) printf("# Ignore ref copy 0x%x\n", sv);
-       else printf("# Ignore non-sv 0x%x\n", sv);
-#endif
-    }
-  } /* end while */
-  
-  /* Clean up after ourselves */
-  //SvREFCNT_dec(tracking_hash);
-  for( i = 0; i < TRACKING_SLOTS; ++i ) {
-    if( (*tv)[ i ] )
-        Safefree( (*tv)[ i ] );
-  }
-  Safefree( tv );    
-  SvREFCNT_dec(pending_array);
-}
-OUTPUT:
-  RETVAL
-