[Gnash-commit] /srv/bzr/gnash/trunk r11702: Cache resource list size so deciding whether or not to run the collection cycle runs in constant time.

[Sandro Santilli]

------------------------------------------------------------
revno: 11702
committer: Sandro Santilli <address@hidden>
branch nick: trunk
timestamp: Wed 2009-12-16 20:46:46 +0100
message:
  Cache resource list size so deciding whether or not to run the collection 
cycle runs in constant time.
modified:
  libbase/GC.cpp
  libbase/GC.h

=== modified file 'libbase/GC.cpp'
--- a/libbase/GC.cpp    2009-12-15 23:54:32 +0000
+++ b/libbase/GC.cpp    2009-12-16 19:46:46 +0000
@@ -93,12 +93,11 @@
                if ( ! res->isReachable() )
                {
 #if GNASH_GC_DEBUG > 1
-                       log_debug(_("GC: recycling object %p (%s)"),
-                                       res, typeName(*res).c_str());
+                       log_debug(_("GC: recycling object %p (%s)"), res, 
typeName(*res));
 #endif
                        ++deleted;
                        delete res;
-                       i = _resList.erase(i);
+                       i = _resList.erase(i); // _resListSize updated at end 
of loop
                }
                else
                {
@@ -107,6 +106,8 @@
                }
        }
 
+    _resListSize -= deleted;
+
        return deleted;
 }
 
@@ -142,7 +143,7 @@
        //    runtime analisys
        //
 
-       size_t curResCount = _resList.size(); // this is O(n) on GNU stdc++ lib 
!
+       size_t curResCount = _resListSize;
        if ( curResCount <  _lastResCount + maxNewCollectablesCount )
        {
 #if GNASH_GC_DEBUG  > 1
@@ -181,7 +182,7 @@
                        deleted, _lastResCount);
 #endif
 
-       //assert(_lastResCount == _resList.size()); // again O(n)...
+       //assert(_lastResCount == _resList.size()); // O(n)...
 
 }
 

=== modified file 'libbase/GC.h'
--- a/libbase/GC.h      2009-12-15 23:54:32 +0000
+++ b/libbase/GC.h      2009-12-16 19:46:46 +0000
@@ -41,7 +41,7 @@
 //   2 - print a message for every GcResource being registered and being 
deleted
 //   3 - print info about the mark scan 
 //   
-//#define GNASH_GC_DEBUG 1
+#define GNASH_GC_DEBUG 1
 
 #ifdef GNASH_GC_DEBUG
 # include "log.h"
@@ -237,9 +237,9 @@
                //assert(std::find(_resList.begin(), _resList.end(), item) == 
_resList.end());
 #endif
 
-               _resList.push_back(item);
+               _resList.push_back(item); ++_resListSize;
 #if GNASH_GC_DEBUG > 1
-               log_debug(_("GC %p: collectable %p added, num collectables: 
%d"), (void*)this, (void*)item, _resList.size());
+               log_debug(_("GC: collectable %p added, num collectables: %d"), 
item, _resListSize);
 #endif
        }
 
@@ -264,6 +264,7 @@
        /// Create a garbage collector, using the given root
        GC(GcRoot& root)
                :
+               _resListSize(0),
                _root(root),
                _lastResCount(0)
 #ifdef GNASH_GC_DEBUG 
@@ -296,8 +297,15 @@
        ///
        size_t cleanUnreachable();
 
+       /// List of collectable resources
        ResList _resList;
 
+       // Size of the list above, to avoid the
+       // cost of computing it  ..
+       // .. this is O(n) on GNU stdc++ lib !
+       //
+       ResList::size_type _resListSize;
+
        GcRoot& _root;
 
        static GC* _singleton;