diff options
| author | Simon Marlow <marlowsd@gmail.com> | 2009-12-17 22:42:28 +0000 |
|---|---|---|
| committer | Simon Marlow <marlowsd@gmail.com> | 2009-12-17 22:42:28 +0000 |
| commit | 0417404f5d1230c9d291ea9f73e2831121c8ec99 (patch) | |
| tree | 609f1be77f63606772e71ad84c7a92b205baaa9e /includes/Cmm.h | |
| parent | fb783aeaa5bc1cc60e6bb551c1cd01a097b84fad (diff) | |
| download | haskell-0417404f5d1230c9d291ea9f73e2831121c8ec99.tar.gz | |
Fix #650: use a card table to mark dirty sections of mutable arrays
The card table is an array of bytes, placed directly following the
actual array data. This means that array reading is unaffected, but
array writing needs to read the array size from the header in order to
find the card table.
We use a bytemap rather than a bitmap, because updating the card table
must be multi-thread safe. Each byte refers to 128 entries of the
array, but this is tunable by changing the constant
MUT_ARR_PTRS_CARD_BITS in includes/Constants.h.
Diffstat (limited to 'includes/Cmm.h')
| -rw-r--r-- | includes/Cmm.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/includes/Cmm.h b/includes/Cmm.h index 69b5acc5fc..ff91146745 100644 --- a/includes/Cmm.h +++ b/includes/Cmm.h @@ -463,6 +463,9 @@ #define StgFunInfoExtra_bitmap(i) StgFunInfoExtraFwd_bitmap(i) #endif +#define mutArrPtrsCardWords(n) \ + ROUNDUP_BYTES_TO_WDS(((n) + (1 << MUT_ARR_PTRS_CARD_BITS) - 1) >> MUT_ARR_PTRS_CARD_BITS) + /* ----------------------------------------------------------------------------- Voluntary Yields/Blocks |