diff options
Diffstat (limited to 'rts/sm/BlockAlloc.c')
| -rw-r--r-- | rts/sm/BlockAlloc.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/rts/sm/BlockAlloc.c b/rts/sm/BlockAlloc.c index daf9fb0ba1..280ebfc7db 100644 --- a/rts/sm/BlockAlloc.c +++ b/rts/sm/BlockAlloc.c @@ -565,6 +565,9 @@ freeChain_lock(bdescr *bd) RELEASE_SM_LOCK; } +// splitBlockGroup(bd,B) splits bd in two. Afterward, bd will have B +// blocks, and a new block descriptor pointing to the remainder is +// returned. bdescr * splitBlockGroup (bdescr *bd, nat blocks) { @@ -575,16 +578,21 @@ splitBlockGroup (bdescr *bd, nat blocks) } if (bd->blocks > BLOCKS_PER_MBLOCK) { - nat mblocks; + nat low_mblocks, high_mblocks; void *new_mblock; if ((blocks - BLOCKS_PER_MBLOCK) % (MBLOCK_SIZE / BLOCK_SIZE) != 0) { barf("splitLargeBlock: not a multiple of a megablock"); } - mblocks = 1 + (blocks - BLOCKS_PER_MBLOCK) / (MBLOCK_SIZE / BLOCK_SIZE); - new_mblock = (void *) ((P_)MBLOCK_ROUND_DOWN(bd) + mblocks * MBLOCK_SIZE_W); + low_mblocks = 1 + (blocks - BLOCKS_PER_MBLOCK) / (MBLOCK_SIZE / BLOCK_SIZE); + high_mblocks = (bd->blocks - blocks) / (MBLOCK_SIZE / BLOCK_SIZE); + + new_mblock = (void *) ((P_)MBLOCK_ROUND_DOWN(bd) + low_mblocks * MBLOCK_SIZE_W); initMBlock(new_mblock); new_bd = FIRST_BDESCR(new_mblock); - new_bd->blocks = MBLOCK_GROUP_BLOCKS(mblocks); + new_bd->blocks = MBLOCK_GROUP_BLOCKS(high_mblocks); + + ASSERT(blocks + new_bd->blocks == + bd->blocks + BLOCKS_PER_MBLOCK - MBLOCK_SIZE/BLOCK_SIZE); } else { |