* src/vm/global.h: Added defines HDRFLAG_HASH_TAKEN and HDRFLAG_HASH_ATTACHED.

* src/mm/cacao-gc/compact.c (compact_move): Hashcode gets attached to objects
while moving if previously taken.

* src/mm/cacao-gc/heap.c (get_object_size): Attached hashcode might increase
object size.

--HG--
branch : exact-gc

diff --git a/src/mm/cacao-gc/compact.c b/src/mm/cacao-gc/compact.c
index b8332217b58f8c0a51a6d35fd5b4529576176a71..4203de00b89e78227105384ba42a55e25637dfac 100644 (file)
--- a/src/mm/cacao-gc/compact.c
+++ b/src/mm/cacao-gc/compact.c
@@ -281,16 +281,22 @@ void compact_unthread_references(java_objectheader *o, void *new)
    Moves the content (including header) of an object around in memory
 
    NOTE: Memory locations may overlap!
+   NOTE: The size of the object can change by moving it around (hashcode)!
 
    IN:
       old......Old Location of the object before compaction
       new......New Location of the object after compaction
       size.....Size of the object in bytes
 
+   OUT:
+      New size of the object after moving it
+
 *******************************************************************************/
 
-void compact_move(u1 *old, u1 *new, u4 size)
+u4 compact_move(u1 *old, u1 *new, u4 size)
 {
+       s4 hashcode;
+       u4 new_size;
 
        GC_ASSERT(new < old);
 
@@ -315,6 +321,27 @@ void compact_move(u1 *old, u1 *new, u4 size)
                MMOVE(new, old, u1, size);
 
        }
+
+       new_size = size;
+
+       /* check if we need to attach the hashcode to the object */
+       if (GC_TEST_FLAGS((java_objectheader *) new, HDRFLAG_HASH_TAKEN)) {
+
+               /* change the flags accordingly */
+               GC_CLEAR_FLAGS((java_objectheader *) new, HDRFLAG_HASH_TAKEN);
+               GC_SET_FLAGS((java_objectheader *) new, HDRFLAG_HASH_ATTACHED);
+
+               /* attach the hashcode at the end of the object */
+               new_size += SIZEOF_VOID_P;
+               hashcode = (s4) (ptrint) old;
+               *( (s4 *) (new + new_size - SIZEOF_VOID_P) ) = hashcode; /* TODO: clean this up */
+
+               GC_ASSERT(new + SIZEOF_VOID_P < old);
+               GC_LOG( printf("Hash attached: %d (0x%08x) to new object at %p\n", hashcode, hashcode, new); );
+
+       }
+
+       return new_size;
 }
 
 
@@ -335,6 +362,7 @@ void compact_me(rootset_t *rs, regioninfo_t *region)
        u1 *ptr_new;
        java_objectheader *o;
        u4 o_size;
+       u4 o_size_new;
        u4 used;
 
        GC_LOG( dolog("GC: Compaction Phase 1 started ..."); );
@@ -375,6 +403,10 @@ void compact_me(rootset_t *rs, regioninfo_t *region)
 
                        /* object survives, place next object behind it */
                        ptr_new += o_size;
+
+                       /* size might change because of attached hashcode */
+                       if (GC_TEST_FLAGS(o, HDRFLAG_HASH_TAKEN))
+                               ptr_new += SIZEOF_VOID_P;
                }
 
                /* skip to next object */
@@ -412,12 +444,12 @@ void compact_me(rootset_t *rs, regioninfo_t *region)
                        /* unmark the object */
                        GC_CLEAR_MARKED(o);
 
-                       /* move the object */
-                       compact_move(ptr, ptr_new, o_size);
+                       /* move the object (size can change) */
+                       o_size_new = compact_move(ptr, ptr_new, o_size);
 
                        /* object survives, place next object behind it */
-                       ptr_new += o_size;
-                       used += o_size;
+                       ptr_new += o_size_new;
+                       used += o_size_new;
                }
 
                /* skip to next object */

diff --git a/src/mm/cacao-gc/heap.c b/src/mm/cacao-gc/heap.c
index 30dddeda70c931b5db64ff46f0aa34f9c2f8f4e0..d7501b2f0cc3fd72c24c1c48a06e7ed4f6943ec8 100644 (file)
--- a/src/mm/cacao-gc/heap.c
+++ b/src/mm/cacao-gc/heap.c
@@ -76,10 +76,6 @@ void heap_init_objectheader(java_objectheader *o, u4 bytelength)
        /* align the size */
        /* TODO */
 
-       /* set the hash bits in the header */
-       /* TODO: improve this!!! */
-       GC_SET_HASH(o, (s4) o);
-
        /* calculate the wordcount as stored in the header */
     /* TODO: improve this to save wordcount and without header bytes */
     if ((bytelength & 0x03) == 0) {
@@ -153,10 +149,22 @@ s4 heap_get_hashcode(java_objectheader *o)
        if (!o)
                return 0;
 
-       /* TODO: improve this heavily! */
-       hashcode = GC_GET_HASH(o);
+       /* TODO: we need to lock the object here i think!!! */
+
+       /* check if there is a hash attached to this object */
+       if (GC_TEST_FLAGS(o, HDRFLAG_HASH_ATTACHED)) {
+
+               hashcode = *( (s4 *) ( ((u1 *) o) + get_object_size(o) - SIZEOF_VOID_P ) ); /* TODO: clean this up!!! */
+               GC_LOG( printf("Hash re-taken: %d (0x%08x)\n", hashcode, hashcode); );
+
+       } else {
 
-       /*GC_LOG( printf("Hash taken: %d (0x%08x)\n", hashcode, hashcode); );*/
+               GC_SET_FLAGS(o, HDRFLAG_HASH_TAKEN);
+
+               hashcode = (s4) (ptrint) o;
+               GC_LOG( printf("Hash taken: %d (0x%08x)\n", hashcode, hashcode); );
+
+       }
 
        return hashcode;
 }
@@ -272,9 +280,11 @@ void heap_println_usage()
 #if !defined(NDEBUG)
 void heap_print_object_flags(java_objectheader *o)
 {
-       printf("0x%02x 0x%08x [%s%s%s]",
-               GC_GET_SIZE(o), GC_GET_HASH(o),
+       printf("0x%02x [%s%s%s%s%s]",
+               GC_GET_SIZE(o),
                GC_TEST_FLAGS(o, GC_FLAG_FINALIZER)     ? "F" : " ",
+               GC_TEST_FLAGS(o, HDRFLAG_HASH_ATTACHED) ? "A" : " ",
+               GC_TEST_FLAGS(o, HDRFLAG_HASH_TAKEN)    ? "T" : " ",
                GC_TEST_FLAGS(o, GC_FLAG_UNCOLLECTABLE) ? "U" : " ",
                GC_TEST_FLAGS(o, GC_FLAG_MARKED)        ? "M" : " ");
 }
@@ -426,6 +436,10 @@ s4 get_object_size(java_objectheader *o)
        /* align the size */
        o_size = GC_ALIGN(o_size, GC_ALIGN_SIZE);
 
+       /* the hashcode attached to this object might increase the size */
+       if (GC_TEST_FLAGS(o, HDRFLAG_HASH_ATTACHED))
+               o_size += SIZEOF_VOID_P;
+
        return o_size;
 }
 

diff --git a/src/mm/cacao-gc/heap.h b/src/mm/cacao-gc/heap.h
index ae3207396bf49080fa78f05ac8972395f2d5953f..ecff8e70fda4915ee4b80768fa3c35e3a67c6af5 100644 (file)
--- a/src/mm/cacao-gc/heap.h
+++ b/src/mm/cacao-gc/heap.h
@@ -42,7 +42,7 @@
 
 
 /* TODO: maybe move this to global.h */
-#define GC_FLAG_FINALIZER     0x10
+#define GC_FLAG_FINALIZER     0x40
 #define GC_FLAG_UNCOLLECTABLE HDRFLAG_UNCOLLECTABLE
 #define GC_FLAG_MARKED        (HDRFLAG_MARK1 | HDRFLAG_MARK2)
 
@@ -57,12 +57,9 @@
 #if SIZEOF_VOID_P == 8
 # define GC_GET_SIZE(obj)       ((u4) (((obj)->hdrflags >> 56) & 0xff))
 # define GC_SET_SIZE(obj, size) ((obj)->hdrflags |= ((u8) ((size) & 0xff)) << 56)
-# define GC_GET_HASH(obj)       ((obj)->hdrflags)
 #else
 # define GC_GET_SIZE(obj)       ((u4) (((obj)->hdrflags >> 24) & 0xff))
 # define GC_SET_SIZE(obj, size) ((obj)->hdrflags |= ((u4) ((size) & 0xff)) << 24)
-# define GC_GET_HASH(obj)       ((obj)->hdrflags)
-# define GC_SET_HASH(obj, hash) ((obj)->hdrflags |= ((hash) << 8) & 0x00ffff00)
 #endif
 
 

diff --git a/src/vm/global.h b/src/vm/global.h
index aae87b4f22da3405d77ac8be12b366e1c86b7b59..144e77ff681d0b6af8b5d58c53897433ce280740 100644 (file)
--- a/src/vm/global.h
+++ b/src/vm/global.h
@@ -32,7 +32,7 @@
             Joseph Wenninger
             Christian Thalinger
 
-   $Id: global.h 7397 2007-02-23 23:11:41Z michi $
+   $Id: global.h 7400 2007-02-24 01:00:08Z michi $
 
 */
 
@@ -229,6 +229,8 @@ typedef struct java_objectarray java_objectarray;
 #define HDRFLAG_MARK1         0x02
 #define HDRFLAG_MARK2         0x04
 #define HDRFLAG_UNCOLLECTABLE 0x08
+#define HDRFLAG_HASH_TAKEN    0x10
+#define HDRFLAG_HASH_ATTACHED 0x20
 
 struct java_objectheader {             /* header for all objects              */
        struct _vftbl            *vftbl;   /* pointer to virtual function table   */