Remove code that is dead now that we need >= 6.12 to build

[ghc-hetmet.git] / compiler / cmm / OptimizationFuel.hs

diff --git a/compiler/cmm/OptimizationFuel.hs b/compiler/cmm/OptimizationFuel.hs
index 5e400c4..175dcd0 100644 (file)
--- a/compiler/cmm/OptimizationFuel.hs
+++ b/compiler/cmm/OptimizationFuel.hs
@@ -1,3 +1,9 @@
+-- | Optimisation fuel is used to control the amount of work the optimiser does.
+--
+-- Every optimisation step consumes a certain amount of fuel and stops when
+-- it runs out of fuel.  This can be used e.g. to debug optimiser bugs: Run
+-- the optimiser with varying amount of fuel to find out the exact number of
+-- steps where a bug is introduced in the output.
 module OptimizationFuel
     ( OptimizationFuel,  canRewriteWithFuel, maybeRewriteWithFuel, oneLessFuel
     , OptFuelState, initOptFuelState --, setTotalFuel
@@ -17,7 +23,7 @@ import ZipCfg
 --import GHC.Exts (State#)
 import Panic
 import Data.IORef
-import Monad
+import Control.Monad
 import StaticFlags (opt_Fuel)
 import UniqSupply