[project @ 2000-12-07 09:10:32 by simonpj]

[ghc-hetmet.git] / ghc / compiler / coreSyn / CoreUnfold.lhs

diff --git a/ghc/compiler/coreSyn/CoreUnfold.lhs b/ghc/compiler/coreSyn/CoreUnfold.lhs
index 4ed1cb4..102d8bc 100644 (file)
--- a/ghc/compiler/coreSyn/CoreUnfold.lhs
+++ b/ghc/compiler/coreSyn/CoreUnfold.lhs
@@ -20,7 +20,7 @@ module CoreUnfold (
        mkOtherCon, otherCons,
        unfoldingTemplate, maybeUnfoldingTemplate,
        isEvaldUnfolding, isValueUnfolding, isCheapUnfolding, isCompulsoryUnfolding,
-       hasUnfolding, hasSomeUnfolding,
+       hasUnfolding, hasSomeUnfolding, neverUnfold,
 
        couldBeSmallEnoughToInline, 
        certainlyWillInline, 
@@ -190,8 +190,8 @@ sizeExpr bOMB_OUT_SIZE top_args expr
 
     size_up (Note _ body)     = size_up body   -- Notes cost nothing
 
-    size_up (App fun (Type t))  = size_up fun
-    size_up (App fun arg)     = size_up_app fun [arg]
+    size_up (App fun (Type t)) = size_up fun
+    size_up (App fun arg)      = size_up_app fun [arg]
 
     size_up (Lit lit) | litIsDupable lit = sizeOne
                      | otherwise        = sizeN opt_UF_DearOp  -- For lack of anything better
@@ -220,7 +220,7 @@ sizeExpr bOMB_OUT_SIZE top_args expr
 
        (a) It's too eager.  We don't want to inline a wrapper into a
            context with no benefit.  
-           E.g.  \ x. f (x+x)          o point in inlining (+) here!
+           E.g.  \ x. f (x+x)          no point in inlining (+) here!
 
        (b) It's ineffective. Once g's wrapper is inlined, its case-expressions 
            aren't scrutinising arguments any more
@@ -355,8 +355,6 @@ data ExprSize = TooBig
                       FastInt          -- Size to subtract if result is scrutinised 
                                        -- by a case expression
 
-isTooBig TooBig = True
-isTooBig _      = False
 
 maxSize TooBig         _                                 = TooBig
 maxSize _              TooBig                            = TooBig
@@ -376,7 +374,12 @@ conSizeN n      = SizeIs (_ILIT 1) emptyBag (iUnbox n +# _ILIT 1)
 
 primOpSize op n_args
  | not (primOpIsDupable op) = sizeN opt_UF_DearOp
- | not (primOpOutOfLine op) = sizeZero                 -- These are good to inline
+ | not (primOpOutOfLine op) = sizeN (1 - n_args)
+       -- Be very keen to inline simple primops.
+       -- We give a discount of 1 for each arg so that (op# x y z) costs 1.
+       -- I found occasions where we had 
+       --      f x y z = case op# x y z of { s -> (# s, () #) }
+       -- and f wasn't getting inlined
  | otherwise               = sizeOne
 
 buildSize = SizeIs (-2#) emptyBag 4#