union {
struct bdescr_ *back; /* used (occasionally) for doubly-linked lists*/
StgWord *bitmap;
+ StgPtr scan; /* scan pointer for copying GC */
} u;
unsigned int gen_no; /* generation */
struct step_ *step; /* step */
#define BF_LARGE 2
/* Block is pinned */
#define BF_PINNED 4
-/* Block is part of a compacted generation */
-#define BF_COMPACTED 8
+/* Block is to be marked, not copied */
+#define BF_MARKED 8
/* Block is free, and on the free list (TODO: is this used?) */
#define BF_FREE 16
/* Block is executable */
#define BF_EXEC 32
+/* Block contains only a small amount of live data */
+#define BF_FRAGMENTED 64
+/* we know about this block (for finding leaks) */
+#define BF_KNOWN 128
/* Finding the block descriptor for a given block -------------------------- */
void freeGroup_lock(bdescr *p);
void freeChain_lock(bdescr *p);
-/* Round a value to megablocks --------------------------------------------- */
+bdescr * splitBlockGroup (bdescr *bd, nat blocks);
-#define WORDS_PER_MBLOCK (BLOCKS_PER_MBLOCK * BLOCK_SIZE_W)
+/* Round a value to megablocks --------------------------------------------- */
+// We want to allocate an object around a given size, round it up or
+// down to the nearest size that will fit in an mblock group.
INLINE_HEADER StgWord
round_to_mblocks(StgWord words)
{
- if (words > WORDS_PER_MBLOCK) {
- if ((words % WORDS_PER_MBLOCK) < (WORDS_PER_MBLOCK / 2)) {
- words = (words / WORDS_PER_MBLOCK) * WORDS_PER_MBLOCK;
- } else {
- words = ((words / WORDS_PER_MBLOCK) + 1) * WORDS_PER_MBLOCK;
+ if (words > BLOCKS_PER_MBLOCK * BLOCK_SIZE_W) {
+ // first, ignore the gap at the beginning of the first mblock by
+ // adding it to the total words. Then we can pretend we're
+ // dealing in a uniform unit of megablocks.
+ words += FIRST_BLOCK_OFF/sizeof(W_);
+
+ if ((words % MBLOCK_SIZE_W) < (MBLOCK_SIZE_W / 2)) {
+ words = (words / MBLOCK_SIZE_W) * MBLOCK_SIZE_W;
+ } else {
+ words = ((words / MBLOCK_SIZE_W) + 1) * MBLOCK_SIZE_W;
+ }
+
+ words -= FIRST_BLOCK_OFF/sizeof(W_);
}
- }
- return words;
+ return words;
}
#endif /* !CMINUSMINUS */