code changes...fix all of the statistics collection...clean up collection code
[IRC.git] / Robust / src / Runtime / bamboo / multicoregccompact.c
index 050b4d15287c29b9cc032ece0a1e58ea804378cf..49fd3d9364d856c4098987fa5ff3d50e360e9c8f 100644 (file)
@@ -1,35 +1,23 @@
 #ifdef MULTICORE_GC
+#include "structdefs.h"
 #include "multicoregccompact.h"
 #include "runtime_arch.h"
 #include "multicoreruntime.h"
 #include "multicoregarbage.h"
 #include "markbit.h"
+#include "multicoremem_helper.h"
+#include "gcqueue.h"
 
 int gc_countRunningCores() {
   int count=0;
-  for(int i = 0; i < NUMCORES4GC; ++i) {
-    if(gccorestatus[i] != 0) {
+  for(int i = 0; i < NUMCORES4GC; i++) {
+    if(returnedmem[i]) {
       count++;
     }
   }
   return count;
 }
 
-bool gc_checkCoreStatus() {
-  for(int i = 0; i < NUMCORES4GC; ++i) {
-    if(gccorestatus[i] != 0) {
-      return false;
-    }
-  }  
-  return true;
-}
-
-void gc_resetCoreStatus() {
-  for(int i = 0; i < NUMCORES4GC; ++i) {
-    gccorestatus[i] = 1;
-  }
-}
-
 void initOrig_Dst(struct moveHelper * orig,struct moveHelper * to) {
   // init the dst ptr
   to->localblocknum = 0;
@@ -40,7 +28,11 @@ void initOrig_Dst(struct moveHelper * orig,struct moveHelper * to) {
   // init the orig ptr
   orig->localblocknum = 0;
   orig->ptr=orig->base = to->base;
-  orig->bound = orig->base + BLOCKSIZE(orig->localblocknum);
+  orig->bound=orig->base+BLOCKSIZE(orig->localblocknum);
+#ifdef GC_CACHE_ADAPT
+  to->pagebound=to->base+BAMBOO_PAGE_SIZE;
+  orig->pagebound=orig->base+BAMBOO_PAGE_SIZE;
+#endif
 }
 
 void getSpaceLocally(struct moveHelper *to) {
@@ -48,17 +40,124 @@ void getSpaceLocally(struct moveHelper *to) {
   to->localblocknum++;
   BASEPTR(to->base,BAMBOO_NUM_OF_CORE, to->localblocknum);
   to->ptr=to->base;
-  to->bound = to->base + BLOCKSIZE(to->localblocknum);
+  to->bound=to->base+BLOCKSIZE(to->localblocknum);
+#ifdef GC_CACHE_ADAPT
+  to->pagebound=to->base+BAMBOO_PAGE_SIZE;
+#endif
+}
+
+//This function is called on the master core only...and typically by
+//the message interrupt handler
+
+void handleReturnMem_I(unsigned int cnum, void *heaptop) {
+  unsigned int blockindex;
+  BLOCKINDEX(blockindex, heaptop);
+  unsigned INTPTR localblocknum=GLOBALBLOCK2LOCAL(blockindex);
+  //this core is done as far as memory usage is concerned
+  returnedmem[cnum]=0;
+
+  struct blockrecord * blockrecord=&allocationinfo.blocktable[blockindex];
+
+  blockrecord->status=BS_FREE;
+  blockrecord->usedspace=(unsigned INTPTR)(heaptop-OFFSET2BASEVA(blockindex)-gcbaseva);
+  blockrecord->freespace=BLOCKSIZE(localblocknum)-blockrecord->usedspace;
+  /* Update the lowest free block */
+  if (blockindex < allocationinfo.lowestfreeblock) {
+    allocationinfo.lowestfreeblock=blockindex;
+  }
+
+  /* This is our own block...means we should mark other blocks above us as free*/
+  
+  if (cnum==blockrecord->corenum) {
+    unsigned INTPTR nextlocalblocknum=localblocknum+1;
+    for(;nextlocalblocknum<numblockspercore;nextlocalblocknum++) {
+      unsigned INTPTR blocknum=BLOCKINDEX2(cnum, nextlocalblocknum);
+      struct blockrecord * nextblockrecord=&allocationinfo.blocktable[blocknum];
+      nextblockrecord->status=BS_FREE;
+      nextblockrecord->usedspace=0;
+      //this is true because this cannot be the lowest block
+      nextblockrecord->freespace=BLOCKSIZE(1);
+    }
+  }
+
+  //this could be the last one....
+  int count=gc_countRunningCores();
+  if (gcmovepending==count) {
+    // All cores have stopped...hand out memory as necessary to handle all requests
+    handleMemoryRequests_I();
+  } else {
+    //see if returned memory blocks let us resolve requests
+    useReturnedMem(cnum, allocationinfo.lowestfreeblock);
+  }
+}
+
+void useReturnedMem(unsigned int retcorenum, block_t localblockindex) {
+  for(int i=0;i<NUMCORES4GC;i++) {
+    unsigned INTPTR requiredmem=gcrequiredmems[i];
+    if (requiredmem) {
+      unsigned INTPTR desiredmem=maxusefulmems[i];
+      unsigned INTPTR threshold=(desiredmem<MINMEMORYCHUNKSIZE)? desiredmem: MINMEMORYCHUNKSIZE;
+      unsigned INTPTR memcheck=requiredmem>threshold?requiredmem:threshold;
+
+
+      for(block_t nextlocalblocknum=localblockindex;nextlocalblocknum<numblockspercore;nextlocalblocknum++) {
+       unsigned INTPTR blocknum=BLOCKINDEX2(retcorenum, nextlocalblocknum);
+       struct blockrecord * nextblockrecord=&allocationinfo.blocktable[blocknum];
+       if (nextblockrecord->status==BS_FREE) {
+         unsigned INTPTR freespace=nextblockrecord->freespace&~BAMBOO_CACHE_LINE_MASK;
+         if (freespace>=memcheck) {
+           nextblockrecord->status=BS_USED;
+           void *blockptr=OFFSET2BASEVA(blocknum)+gcbaseva;
+           unsigned INTPTR usedspace=((nextblockrecord->usedspace-1)&~BAMBOO_CACHE_LINE_MASK)+BAMBOO_CACHE_LINE_SIZE;
+           //taken care of one block
+           gcmovepending--;
+           void *startaddr=blockptr+usedspace;
+           gcrequiredmems[i]=0;
+           maxusefulmems[i]=0;
+           if (i==STARTUPCORE) {
+             gctomove = true;
+             gcmovestartaddr = startaddr;
+           } else if(BAMBOO_CHECK_SEND_MODE()) {
+             cache_msg_2_I(i,GCMOVESTART,startaddr);
+           } else {
+             send_msg_2_I(i,GCMOVESTART,startaddr);
+           }
+         }
+       }
+      }
+    }
+  }
+}
+
+void handleReturnMem(unsigned int cnum, void *heaptop) {
+  BAMBOO_ENTER_RUNTIME_MODE_FROM_CLIENT();
+  handleReturnMem_I(cnum, heaptop);
+  BAMBOO_ENTER_CLIENT_MODE_FROM_RUNTIME();
 }
 
 void getSpaceRemotely(struct moveHelper *to, unsigned int minimumbytes) {
   //need to get another block from elsewhere
   //set flag to wait for memory
-  gctomove=false;
-  //send request for memory
-  send_msg_3(STARTUPCORE,GCFINISHCOMPACT,BAMBOO_NUM_OF_CORE, minimumbytes);
-  //wait for flag to be set that we received message
-  while(!gctomove) ;
+
+  if (BAMBOO_NUM_OF_CORE==STARTUPCORE) {
+    gctomove=false;
+    BAMBOO_ENTER_RUNTIME_MODE_FROM_CLIENT();
+    void *startaddr=handlegcfinishcompact_I(BAMBOO_NUM_OF_CORE, minimumbytes, gccurr_heaptop);
+    BAMBOO_ENTER_CLIENT_MODE_FROM_RUNTIME();
+
+    if (startaddr) {
+      gcmovestartaddr=startaddr;
+    } else {
+      while(!gctomove) ;
+    }
+  } else {
+    gctomove=false;
+    //send request for memory
+    send_msg_4(STARTUPCORE,GCFINISHCOMPACT,BAMBOO_NUM_OF_CORE, minimumbytes, gccurr_heaptop);
+    //wait for flag to be set that we received message
+    while(!gctomove)
+      ;
+  }
 
   //store pointer
   to->ptr = gcmovestartaddr;
@@ -68,12 +167,15 @@ void getSpaceRemotely(struct moveHelper *to, unsigned int minimumbytes) {
   unsigned int globalblocknum;
   BLOCKINDEX(globalblocknum, to->ptr);
   to->base = gcbaseva + OFFSET2BASEVA(globalblocknum);
-  to->bound = gcbaseva + BOUNDPTR(globalblocknum);
+  to->bound=gcbaseva+BOUNDPTR(globalblocknum);
+#ifdef GC_CACHE_ADAPT
+  to->pagebound=(void *)((int)((int)(to->ptr)&(~(BAMBOO_PAGE_SIZE-1)))+BAMBOO_PAGE_SIZE);
+#endif
 }
 
 void getSpace(struct moveHelper *to, unsigned int minimumbytes) {
   //need more space to compact into
-  if (to->localblocknum < gcblock2fill) {
+  if ((to->localblocknum+1) < gcblock2fill) {
     getSpaceLocally(to);
   } else {
     getSpaceRemotely(to, minimumbytes);
@@ -83,44 +185,59 @@ void getSpace(struct moveHelper *to, unsigned int minimumbytes) {
 void compacthelper(struct moveHelper * orig,struct moveHelper * to) {
   bool senttopmessage=false;
   while(true) {
-    if ((gcheaptop < ((unsigned INTPTR)(to->bound-to->ptr)))&&!senttopmessage) {
+    if ((gccurr_heaptop <= ((unsigned INTPTR)(to->bound-to->ptr)))&&!senttopmessage) {
       //This block is the last for this core...let the startup know
-      send_msg_3(STARTUPCORE, GCRETURNMEM, BAMBOO_NUM_OF_CORE, to->ptr+gcheaptop);
+      if (BAMBOO_NUM_OF_CORE==STARTUPCORE) {
+       handleReturnMem(BAMBOO_NUM_OF_CORE, to->ptr+gccurr_heaptop);
+      } else {
+       send_msg_3(STARTUPCORE, GCRETURNMEM, BAMBOO_NUM_OF_CORE, to->ptr+gccurr_heaptop);
+      }
       //Only send the message once
       senttopmessage=true;
     }
-
-    unsigned int minimumbytes=compactblocks(orig, to);
+    unsigned int minimumbytes=COMPACTUNITS(orig, to);
     if (orig->ptr==orig->bound) {
       //need more data to compact
       //increment the core
       orig->localblocknum++;
       BASEPTR(orig->base,BAMBOO_NUM_OF_CORE, orig->localblocknum);
       orig->ptr=orig->base;
-      orig->bound = orig->base + BLOCKSIZE(orig->localblocknum);
-      if (orig->base >= gcbaseva+BAMBOO_SHARED_MEM_SIZE)
+      orig->bound=orig->base+BLOCKSIZE(orig->localblocknum);
+#ifdef GC_CACHE_ADAPT
+      orig->pagebound=orig->base+BAMBOO_PAGE_SIZE;
+#endif
+      if (orig->base >= gcbaseva+BAMBOO_SHARED_MEM_SIZE) {
+       CACHEADAPT_FINISH_COMPACT(to->ptr);
        break;
+      }
     }
     if (minimumbytes!=0) {
       getSpace(to, minimumbytes);
     }
   }
-  
-  send_msg_3(STARTUPCORE,GCFINISHCOMPACT,BAMBOO_NUM_OF_CORE, 0);
+  if (BAMBOO_NUM_OF_CORE==STARTUPCORE) {
+    BAMBOO_ENTER_RUNTIME_MODE_FROM_CLIENT();
+    handlegcfinishcompact_I(BAMBOO_NUM_OF_CORE, 0, 0);
+    BAMBOO_ENTER_CLIENT_MODE_FROM_RUNTIME();
+  } else {
+    send_msg_4(STARTUPCORE,GCFINISHCOMPACT,BAMBOO_NUM_OF_CORE, 0, 0);
+  }
 }
 
-void * checkNeighbors(int corenum, unsigned INTPTR requiredmem) {
-  int minblockindex=allocation.lowestfreeblock/NUMCORES4GC;
-  block_t toplocalblock=topblock/NUMCORES4GC;
-  for(int i=0;i<NUM_CORES2TEST;i++) {
-    int neighborcore=core2test[corenum][i];
-    if (neighborcore!=-1) {
-      for(block_t lblock=minblockindex;lblock<numblockspercore;lblock++) {
+void * checkNeighbors_I(int ncorenum, unsigned INTPTR requiredmem, unsigned INTPTR desiredmem) {
+  int minblockindex=allocationinfo.lowestfreeblock/NUMCORES4GC;
+  unsigned INTPTR threshold=(desiredmem<MINMEMORYCHUNKSIZE)? desiredmem: MINMEMORYCHUNKSIZE;
+  unsigned INTPTR memcheck=requiredmem>threshold?requiredmem:threshold;
+
+  for(block_t lblock=minblockindex;lblock<numblockspercore;lblock++) {
+    for(int i=0;i<NUM_CORES2TEST;i++) {
+      int neighborcore=core2test[ncorenum][i];
+      if (neighborcore!=-1) {
        block_t globalblockindex=BLOCKINDEX2(neighborcore, lblock);
        struct blockrecord * block=&allocationinfo.blocktable[globalblockindex];
        if (block->status==BS_FREE) {
          unsigned INTPTR freespace=block->freespace&~BAMBOO_CACHE_LINE_MASK;
-         if (requiredmem<freespace) {
+         if (memcheck<=freespace) {
            //we have a block
            //mark block as used
            block->status=BS_USED;
@@ -135,19 +252,22 @@ void * checkNeighbors(int corenum, unsigned INTPTR requiredmem) {
   return NULL;
 }
 
-void * globalSearch(unsigned int topblock) {
+void * globalSearch_I(unsigned int topblock, unsigned INTPTR requiredmem, unsigned INTPTR desiredmem) {
   unsigned int firstfree=NOFREEBLOCK;
+  unsigned INTPTR threshold=(desiredmem<MINMEMORYCHUNKSIZE)? desiredmem: MINMEMORYCHUNKSIZE;
+  unsigned INTPTR memcheck=requiredmem>threshold?requiredmem:threshold;
+
   for(block_t i=allocationinfo.lowestfreeblock;i<topblock;i++) {
     struct blockrecord * block=&allocationinfo.blocktable[i];
     if (block->status==BS_FREE) {
       if(firstfree==NOFREEBLOCK)
        firstfree=i;
       unsigned INTPTR freespace=block->freespace&~BAMBOO_CACHE_LINE_MASK;
-      if (requiredmem<freespace) {
+      if (memcheck<=freespace) {
        //we have a block
        //mark block as used
        block->status=BS_USED;
-       void *blockptr=OFFSET2BASEVA(globalblockindex)+gcbaseva;
+       void *blockptr=OFFSET2BASEVA(i)+gcbaseva;
        unsigned INTPTR usedspace=((block->usedspace-1)&~BAMBOO_CACHE_LINE_MASK)+BAMBOO_CACHE_LINE_SIZE;
        allocationinfo.lowestfreeblock=firstfree;
        return blockptr+usedspace;
@@ -158,49 +278,145 @@ void * globalSearch(unsigned int topblock) {
   return NULL;
 }
 
+void handleOneMemoryRequest(int core, unsigned int lowestblock) {
+  unsigned INTPTR requiredmem=gcrequiredmems[core];
+  unsigned INTPTR desiredmem=maxusefulmems[core];
+  block_t firstfree=NOFREEBLOCK;
+  unsigned INTPTR threshold=(desiredmem<MINMEMORYCHUNKSIZE)? desiredmem: MINMEMORYCHUNKSIZE;
+  unsigned INTPTR memcheck=requiredmem>threshold?requiredmem:threshold;
+
+  for(block_t searchblock=lowestblock;searchblock<GCNUMBLOCK;searchblock++) {
+    struct blockrecord * block=&allocationinfo.blocktable[searchblock];
+    if (block->status==BS_FREE) {
+      if(firstfree==NOFREEBLOCK)
+       firstfree=searchblock;
+      //don't take a block from another core that hasn't returned its memory yet
+      if (block->corenum!=core&&returnedmem[block->corenum])
+       continue;
+      
+      unsigned INTPTR freespace=block->freespace&~BAMBOO_CACHE_LINE_MASK;
+      if (freespace>=memcheck) {
+       //TODO: should check memory block at same level on our own core...if that works, use it to preserve locality
+
+       //we have a block
+       //mark block as used
+       block->status=BS_USED;
+       void *blockptr=OFFSET2BASEVA(searchblock)+gcbaseva;
+       unsigned INTPTR usedspace=((block->usedspace-1)&~BAMBOO_CACHE_LINE_MASK)+BAMBOO_CACHE_LINE_SIZE;
+       allocationinfo.lowestfreeblock=firstfree;
+       //taken care of one block
+       gcmovepending--;
+       void *startaddr=blockptr+usedspace;
+       if(BAMBOO_CHECK_SEND_MODE()) {
+         cache_msg_2_I(core,GCMOVESTART,startaddr);
+       } else {
+         send_msg_2_I(core,GCMOVESTART,startaddr);
+       }
+       return;
+      }
+    }
+  }
+  //this is bad...ran out of memory
+  printf("Out of memory.  Was trying for %u bytes\n", threshold);
+  BAMBOO_EXIT();
+}
+
+void handleMemoryRequests_I() {
+  unsigned int lowestblock=allocationinfo.lowestfreeblock;
+  if (lowestblock==NOFREEBLOCK) {
+    lowestblock=numblockspercore*NUMCORES4GC;
+  }
+  
+  for(int i=0;i < NUMCORES4GC; i++) {
+    if (gcrequiredmems[i]) {
+      handleOneMemoryRequest(i, lowestblock);
+      lowestblock=allocationinfo.lowestfreeblock;
+    }
+  }
+}
+
 /* should be invoked with interrupt turned off */
 
-void * gcfindSpareMem_I(unsigned int requiredmem,unsigned int requiredcore) {
+void * gcfindSpareMem_I(unsigned INTPTR requiredmem, unsigned INTPTR desiredmem,unsigned int requiredcore) {
   if (allocationinfo.lowestfreeblock!=NOFREEBLOCK) {
     //There are spare blocks
     unsigned int topblock=numblockspercore*NUMCORES4GC;
     void *memblock;
     
-    if (memblock=checkNeighbors(requiredcore, requiredmem)) {
+    if (memblock=checkNeighbors_I(requiredcore, requiredmem, desiredmem)) {
       return memblock;
-    } else if (memblock=globalSearch(topblock, requiredmem)) {
+    } else if (memblock=globalSearch_I(topblock, requiredmem, desiredmem)) {
       return memblock;
     }
   }
   
   // If we cannot find spare mem right now, hold the request
   gcrequiredmems[requiredcore] = requiredmem;
+  maxusefulmems[requiredcore]=desiredmem;
   gcmovepending++;
 
   int count=gc_countRunningCores();
   if (gcmovepending==count) {
     // All cores have stopped...hand out memory as necessary to handle all requests
-    
+    handleMemoryRequests_I();
   }
 
   return NULL;
 } 
 
-bool gcfindSpareMem(unsigned int requiredmem,unsigned int requiredcore) {
-  BAMBOO_ENTER_RUNTIME_MODE_FROM_CLIENT();
-  bool retval=gcfindSpareMem_I(requiredmem, requiredcore);
-  BAMBOO_ENTER_CLIENT_MODE_FROM_RUNTIME();
-  return retval;
+#ifdef GC_CACHE_ADAPT
+unsigned int compactblockshelper(struct moveHelper * orig, struct moveHelper * to) {
+  unsigned int minimumbytes=0;
+  void *origptr=orig->ptr;
+  void *origbound=orig->bound;
+  void * tmporig=orig->ptr;
+  void * tmpto=to->ptr;
+
+  while(true) {
+    //call compactblocks using the page boundaries at the current bounds
+    minimumbytes=compactblocks(orig, to);
+    if(minimumbytes == 0) {
+      //bump the orig page bound...
+      //use old orig pointer to make sure we get correct block
+      CACHEADAPT_FINISH_SRC_PAGE(tmporig, tmpto, to->ptr);
+      if (orig->ptr<origbound) {
+       tmporig=orig->ptr;
+       tmpto=to->ptr;
+       orig->pagebound=orig->pagebound+BAMBOO_PAGE_SIZE;
+      } else {
+       return 0;
+      }
+    } else {
+      // require more memory
+      void *endtoptr=to->ptr+minimumbytes;
+      if (endtoptr>to->bound) {
+       CACHEADAPT_FINISH_DST_PAGE(orig->ptr, tmpto, to->ptr, 0);
+       return minimumbytes;
+      } else {
+       CACHEADAPT_FINISH_DST_PAGE(orig->ptr, tmpto, to->ptr, minimumbytes);
+       to->pagebound=((((unsigned INTPTR)endtoptr)-1)&~(BAMBOO_PAGE_SIZE-1))+BAMBOO_PAGE_SIZE;
+       //update pointers to avoid double counting the stuff we already added in
+       tmporig=orig->ptr+minimumbytes;
+       tmpto=to->ptr+minimumbytes;
+      }
+    }
+  }
 }
+#endif
 
 /* This function is performance critical...  spend more time optimizing it */
 
 unsigned int compactblocks(struct moveHelper * orig, struct moveHelper * to) {
   void *toptrinit=to->ptr;
-  void *toptr=toptr;
-  void *tobound=to->bound;
+  void *toptr=toptrinit;
   void *origptr=orig->ptr;
+#ifdef GC_CACHE_ADAPT
+  void *origbound=orig->pagebound;
+  void *tobound=to->pagebound;
+#else
   void *origbound=orig->bound;
+  void *tobound=to->bound;
+#endif
   unsigned INTPTR origendoffset=ALIGNTOTABLEINDEX((unsigned INTPTR)(origbound-gcbaseva));
   unsigned int objlength;
 
@@ -211,50 +427,71 @@ unsigned int compactblocks(struct moveHelper * orig, struct moveHelper * to) {
     if (!gcmarktbl[arrayoffset]) {
       do {
        arrayoffset++;
-       if (arrayoffset<origendoffset) {
-         //finished with block...
-         origptr=origbound;
+       if (arrayoffset>=origendoffset) {
+         //finished with block(a page in CACHE_ADAPT version)...
          to->ptr=toptr;
-         orig->ptr=origptr;
-         gcheaptop-=(unsigned INTPTR)(toptr-toptrinit)
+         orig->ptr=origbound;
+         gccurr_heaptop-=(unsigned INTPTR)(toptr-toptrinit);
          return 0;
        }
       } while(!gcmarktbl[arrayoffset]);
       origptr=CONVERTTABLEINDEXTOPTR(arrayoffset);
     }
-
+    
     //Scan more carefully next
     objlength=getMarkedLength(origptr);
 
     if (objlength!=NOTMARKED) {
       unsigned int length=ALIGNSIZETOBYTES(objlength);
+
+      //code between this and next comment should be removed
+#ifdef GC_DEBUG
+      unsigned int size;
+      unsigned int type;
+      gettype_size(origptr, &type, &size);
+      size=((size-1)&(~(ALIGNMENTSIZE-1)))+ALIGNMENTSIZE;
+      
+      if (size!=length) {
+       tprintf("BAD SIZE IN BITMAP: type=%u object=%x size=%u length=%u\n", type, origptr, size, length);
+       unsigned INTPTR alignsize=ALIGNOBJSIZE((unsigned INTPTR)(origptr-gcbaseva));
+       unsigned INTPTR hibits=alignsize>>4;
+       unsigned INTPTR lobits=(alignsize&15)<<1;
+       tprintf("hibits=%x lobits=%x\n", hibits, lobits);
+       tprintf("hi=%x lo=%x\n", gcmarktbl[hibits], gcmarktbl[hibits+1]);
+      }
+#endif
+      //end of code to remove
+
       void *endtoptr=toptr+length;
       if (endtoptr>tobound) {
-       gcheaptop-=(unsigned INTPTR)(toptr-toptrinit)   
-       to->ptr=tobound;
+       gccurr_heaptop-=(unsigned INTPTR)(toptr-toptrinit);
+       to->ptr=toptr;
        orig->ptr=origptr;
        return length;
       }
       //good to move objects and update pointers
+      
       gcmappingtbl[OBJMAPPINGINDEX(origptr)]=toptr;
+      
       origptr+=length;
       toptr=endtoptr;
     } else
       origptr+=ALIGNMENTSIZE;
   }
+  to->ptr=toptr;
+  orig->ptr=origptr;
+  gccurr_heaptop-=(unsigned INTPTR)(toptr-toptrinit);
+  return 0;
 }
 
 void compact() {
   BAMBOO_ASSERT(COMPACTPHASE == gc_status_info.gcphase);
-  BAMBOO_CACHE_MF();
   
   // initialize structs for compacting
-  struct moveHelper orig={0,NULL,NULL,0,NULL,0,0,0,0};
-  struct moveHelper to={0,NULL,NULL,0,NULL,0,0,0,0};
+  struct moveHelper orig;
+  struct moveHelper to;
   initOrig_Dst(&orig, &to);
 
-  CACHEADAPT_SAMPLING_DATA_REVISE_INIT(&orig, &to);
-
   compacthelper(&orig, &to);
 } 
 
@@ -267,7 +504,7 @@ void master_compact() {
   gc_resetCoreStatus();
   //initialize local data structures first....we don't want remote requests messing data up
   unsigned int initblocks=numblockspercore*NUMCORES4GC;
-  allocationinfo.lowestfreeblock=NOFREEBLOCKS;
+  allocationinfo.lowestfreeblock=NOFREEBLOCK;
 
   //assigned blocks
   for(int i=0;i<initblocks;i++) {
@@ -287,6 +524,7 @@ void master_compact() {
     // init some data strutures for compact phase
     gcrequiredmems[i] = 0;
     gccorestatus[i] = 1;
+    returnedmem[i] = 1;
     //send start compact messages to all cores
     if(i != STARTUPCORE) {
       send_msg_2(i, GCSTARTCOMPACT, numblockspercore);
@@ -294,17 +532,56 @@ void master_compact() {
       gcblock2fill = numblockspercore;
     }
   }
-  BAMBOO_CACHE_MF();
   GCPROFILE_ITEM();
   // compact phase
   compact();
   /* wait for all cores to finish compacting */
+  
 
-  while(gc_checkCoreStatus())
+  while(!gc_checkCoreStatus())
     ;
 
+#ifdef GC_DEBUG
+  void *nextvalid=gcbaseva;
+  for(void *tmp=gcbaseva; tmp<gcbaseva+BAMBOO_SHARED_MEM_SIZE;tmp+=ALIGNMENTSIZE) {
+    unsigned int objlength=getMarkedLength(tmp);
+    void *forwarding=gcmappingtbl[OBJMAPPINGINDEX(tmp)];
+    if (tmp>=nextvalid&&((objlength!=0)!=(forwarding!=NULL))) {
+      tprintf("Maps disagree tmp=%x olength=%u forwarding=%x\n",tmp, objlength, forwarding);
+    }
+    if (tmp<nextvalid&&forwarding!=NULL) {
+      tprintf("Weird forwarding pointer\n");
+    }
+    if (tmp>=nextvalid&&(objlength!=0||forwarding!=NULL)) {
+      unsigned int length=ALIGNSIZETOBYTES(objlength);
+      unsigned int size;
+      unsigned int type;
+      nextvalid=tmp+length;
+      gettype_size(tmp, &type, &size);
+      size=((size-1)&(~(ALIGNMENTSIZE-1)))+ALIGNMENTSIZE;
+      if (size!=length) {
+       tprintf("Bad size in bitmap: tmp=%x length=%u size=%u type=%u\n", tmp, length, size, type);
+      }
+      block_t blockindex;
+      BLOCKINDEX(blockindex, forwarding);
+      struct blockrecord * block=&allocationinfo.blocktable[blockindex];
+      void *blockptr=OFFSET2BASEVA(blockindex)+gcbaseva;
+
+      if (block->status==BS_FREE) {
+       if (forwarding>(blockptr+block->usedspace)) {
+         tprintf("Pointer references free space forwarding=%x tmp=%x length=%u type=%u blockindex=%u, baseptr=%x, usedspace=%u, status=%u\n", forwarding, tmp, length, type,blockindex, blockptr, block->usedspace, block->status);
+       }
+      }
+    }
+  }
+#endif
+
   GCPROFILE_ITEM();
 
+  //just in case we didn't get blocks back...
+  if (allocationinfo.lowestfreeblock==NOFREEBLOCK)
+    allocationinfo.lowestfreeblock=numblockspercore*NUMCORES4GC;
+
   GC_PRINTF("compact phase finished \n");
 }