[commit: ghc] new-demand: rearrangements (9bef451)

[Ilya Sergey]

Repository : ssh://darcs.haskell.org//srv/darcs/ghc

On branch  : new-demand

http://hackage.haskell.org/trac/ghc/changeset/9bef451676def6338b250f62b5eb0b4674aab990

>---------------------------------------------------------------

commit 9bef451676def6338b250f62b5eb0b4674aab990
Author: Ilya Sergey <Ilya.Sergey at cs.kuleuven.be>
Date:   Mon Jul 16 19:30:32 2012 +0100

    rearrangements

>---------------------------------------------------------------

 compiler/basicTypes/NewDemand.lhs |   10 ++++------
 1 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/compiler/basicTypes/NewDemand.lhs b/compiler/basicTypes/NewDemand.lhs
index e9d2741..53fbdbd 100644
--- a/compiler/basicTypes/NewDemand.lhs
+++ b/compiler/basicTypes/NewDemand.lhs
@@ -644,15 +644,13 @@ instance LatticeLike DmdType where
 
   lub (DmdType fv1 ds1 r1) (DmdType fv2 ds2 r2)
     = DmdType lub_fv2 (lub_ds ds1 ds2) (r1 `lub` r2)
-    -- Consider (if x then y else []) with demand V
-    -- Then the first branch gives {y->V} and the second
-    --  *implicitly* has {y->A}.  So we must put {y->(V `lub` A)}
-    -- in the result env.
     where
       absLub  = lub absDmd
       lub_fv  = plusVarEnv_C lub fv1 fv2
-      -- TODO: write down an example
-      -- TODO: compute a lub-candidate from r1 and r2
+      -- Consider (if x then y else []) with demand V
+      -- Then the first branch gives {y->V} and the second
+      -- *implicitly* has {y->A}.  So we must put {y->(V `lub` A)}
+      -- in the result env.
       lub_fv1 = modifyEnv (not (isBotRes r1)) absLub fv2 fv1 lub_fv
       lub_fv2 = modifyEnv (not (isBotRes r2)) absLub fv1 fv2 lub_fv1
 	-- lub is the identity for Bot