diff options
Diffstat (limited to 'rts/Updates.cmm')
| -rw-r--r-- | rts/Updates.cmm | 100 |
1 files changed, 66 insertions, 34 deletions
diff --git a/rts/Updates.cmm b/rts/Updates.cmm index e0fd7c30d5..7af59657c1 100644 --- a/rts/Updates.cmm +++ b/rts/Updates.cmm @@ -16,10 +16,11 @@ #include "Updates.h" -/* on entry to the update code - (1) R1 points to the closure being returned - (2) Sp points to the update frame -*/ +#if defined(PROFILING) +#define UPD_FRAME_PARAMS W_ unused1, W_ unused2, P_ unused3 +#else +#define UPD_FRAME_PARAMS P_ unused1 +#endif /* The update fragment has been tuned so as to generate good code with gcc, which accounts for some of the strangeness in the @@ -30,38 +31,69 @@ code), since we don't mind duplicating this jump. */ -#define UPD_FRAME_ENTRY_TEMPLATE \ - { \ - W_ updatee; \ - \ - updatee = StgUpdateFrame_updatee(Sp); \ - \ - /* remove the update frame from the stack */ \ - Sp = Sp + SIZEOF_StgUpdateFrame; \ - \ - /* ToDo: it might be a PAP, so we should check... */ \ - TICK_UPD_CON_IN_NEW(sizeW_fromITBL(%GET_STD_INFO(updatee))); \ - \ - updateWithIndirection(stg_IND_direct_info, \ - updatee, \ - R1, \ - jump %ENTRY_CODE(Sp(0))); \ - } - -#if defined(PROFILING) -#define UPD_FRAME_PARAMS W_ unused1, W_ unused2, P_ unused3 -#else -#define UPD_FRAME_PARAMS P_ unused1 -#endif - -/* this bitmap indicates that the first word of an update frame is a - * non-pointer - this is the update frame link. (for profiling, - * there's a cost-centre-stack in there too). - */ +/* on entry to the update code + (1) R1 points to the closure being returned + (2) Sp points to the update frame +*/ INFO_TABLE_RET( stg_upd_frame, UPDATE_FRAME, UPD_FRAME_PARAMS) -UPD_FRAME_ENTRY_TEMPLATE +{ + W_ updatee; + + updatee = StgUpdateFrame_updatee(Sp); + + /* remove the update frame from the stack */ + Sp = Sp + SIZEOF_StgUpdateFrame; + + /* ToDo: it might be a PAP, so we should check... */ + TICK_UPD_CON_IN_NEW(sizeW_fromITBL(%GET_STD_INFO(updatee))); + + updateWithIndirection(updatee, + R1, + jump %ENTRY_CODE(Sp(0))); +} INFO_TABLE_RET( stg_marked_upd_frame, UPDATE_FRAME, UPD_FRAME_PARAMS) -UPD_FRAME_ENTRY_TEMPLATE +{ + W_ updatee, v, i, tso, link; + + // we know the closure is a BLACKHOLE + updatee = StgUpdateFrame_updatee(Sp); + v = StgInd_indirectee(updatee); + + // remove the update frame from the stack + Sp = Sp + SIZEOF_StgUpdateFrame; + + if (GETTAG(v) != 0) { + // updated by someone else: discard our value and use the + // other one to increase sharing, but check the blocking + // queues to see if any threads were waiting on this BLACKHOLE. + R1 = v; + foreign "C" checkBlockingQueues(MyCapability() "ptr", + CurrentTSO "ptr") [R1]; + jump %ENTRY_CODE(Sp(0)); + } + + // common case: it is still our BLACKHOLE + if (v == CurrentTSO) { + updateWithIndirection(updatee, + R1, + jump %ENTRY_CODE(Sp(0))); + } + + // The other cases are all handled by the generic code + foreign "C" updateThunk (MyCapability() "ptr", CurrentTSO "ptr", + updatee "ptr", R1 "ptr") [R1]; + + jump %ENTRY_CODE(Sp(0)); +} + +// Special update frame code for CAFs and eager-blackholed thunks: it +// knows how to update blackholes, but is distinct from +// stg_marked_upd_frame so that lazy blackholing won't treat it as the +// high watermark. +INFO_TABLE_RET (stg_bh_upd_frame, UPDATE_FRAME, UPD_FRAME_PARAMS) +{ + jump stg_marked_upd_frame_info; +} |