X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FdeSugar%2FDsExpr.lhs;h=043f54fa8066f491968487ea1b50355be150a329;hb=620531f5074b189bd04d10c88196493b1e2fa692;hp=0633717d09538b9f0f1077a42729eb7efa4e3731;hpb=6febb616f1ff46942434e9df39c6e4977b07cc6f;p=ghc-hetmet.git

diff --git a/compiler/deSugar/DsExpr.lhs b/compiler/deSugar/DsExpr.lhs
index 0633717..043f54f 100644
--- a/compiler/deSugar/DsExpr.lhs
+++ b/compiler/deSugar/DsExpr.lhs
@@ -42,6 +42,7 @@ import TcType
 import Type
 import CoreSyn
 import CoreUtils
+import MkCore
 
 import DynFlags
 import CostCentre
@@ -211,7 +212,7 @@ dsExpr (HsLam a_Match)
   = uncurry mkLams <$> matchWrapper LambdaExpr a_Match
 
 dsExpr (HsApp fun arg)
-  = mkDsApp <$> dsLExpr fun <*>  dsLExpr arg
+  = mkCoreApp <$> dsLExpr fun <*>  dsLExpr arg
 \end{code}
 
 Operator sections.  At first it looks as if we can convert
@@ -238,10 +239,10 @@ will sort it out.
 \begin{code}
 dsExpr (OpApp e1 op _ e2)
   = -- for the type of y, we need the type of op's 2nd argument
-    mkDsApps <$> dsLExpr op <*> mapM dsLExpr [e1, e2]
+    mkCoreApps <$> dsLExpr op <*> mapM dsLExpr [e1, e2]
     
 dsExpr (SectionL expr op)	-- Desugar (e !) to ((!) e)
-  = mkDsApp <$> dsLExpr op <*> dsLExpr expr
+  = mkCoreApp <$> dsLExpr op <*> dsLExpr expr
 
 -- dsLExpr (SectionR op expr)	-- \ x -> op x expr
 dsExpr (SectionR op expr) = do
@@ -253,7 +254,7 @@ dsExpr (SectionR op expr) = do
     x_id <- newSysLocalDs x_ty
     y_id <- newSysLocalDs y_ty
     return (bindNonRec y_id y_core $
-            Lam x_id (mkDsApps core_op [Var x_id, Var y_id]))
+            Lam x_id (mkCoreApps core_op [Var x_id, Var y_id]))
 
 dsExpr (HsSCC cc expr) = do
     mod_name <- getModuleDs
@@ -505,10 +506,8 @@ dsExpr (HsBinTick ixT ixF e) = do
 
 \begin{code}
 
-#ifdef DEBUG
 -- HsSyn constructs that just shouldn't be here:
 dsExpr (ExprWithTySig _ _)  = panic "dsExpr:ExprWithTySig"
-#endif
 
 
 findField :: [HsRecField Id arg] -> Name -> [arg]
@@ -541,13 +540,18 @@ fruitless allocations.  Essentially, whenever we see a list literal
    
    If fusion fails to occur then build will get inlined and (since we
    defined a RULE for foldr (:) []) we will get back exactly the
-   normal desugaring for an explicit list! However, if it does occur
-   then we can potentially save quite a bit of allocation (up to 25\%
-   of the total in some nofib programs!)
+   normal desugaring for an explicit list.
+
+This optimisation can be worth a lot: up to 25% of the total
+allocation in some nofib programs. Specifically
+
+        Program           Size    Allocs   Runtime  CompTime
+        rewrite          +0.0%    -26.3%      0.02     -1.8%
+           ansi          -0.3%    -13.8%      0.00     +0.0%
+           lift          +0.0%     -8.7%      0.00     -2.3%
 
 Of course, if rules aren't turned on then there is pretty much no
 point doing this fancy stuff, and it may even be harmful.
-
 \begin{code}
 
 dsExplicitList :: PostTcType -> [LHsExpr Id] -> DsM CoreExpr