I noticed some suspicious wiggling in my ticky reports' entry counts. SPJ suggested they were due to the counter ticking before the heap check: if it fails, then it ticks again when we re-enter after the stg_gc function does its thing.

 

After looking into it a bit further, I have a couple questions. Here's what I found.

 

  * for functions (StgCmmBind.closureCodeBody), tickyEnterFun and enterCostCentreFun are before the heap check

 

  * for thunks (StgCmmBind.thunkCode), tickyEnterThunk is before the heap check and enterCostCentreThunk is after.

 

Questions:

 

  * Does any object to me moving both ticky counters after the heap check?

 

  * Is there a reason the two cost centre profiling entries are on opposite sides of the heap check?

 

Thanks.