[PATCH] D21189: Create subranges for new intervals resulting from live interval splitting

[Krzysztof Parzyszek via llvm-commits]

kparzysz added a comment.

Please disregard the previous comment with these statistics---I forgot to enable subregister liveness tracking in that experiment.

Regarding the complexity of isDefOnEntry, I have collected some statistics: between each time a LiveRangeCalc object is created/reset and reset/destroyed, I counted how many times each particular basic block is added to the work list.  Then I divided that number by the number of distinct blocks that were added to the worklist.  This would give an average number of visits for each block that has been visited.
For a customer code with over 20,000 functions, this code was executed 647 times (i.e. 647 times there was a lifespan of a LiveRangeCalc objects when at least one block was visited).  The average visit count over all such lifespans was 1.19.


Repository:
  rL LLVM

https://reviews.llvm.org/D21189