[project @ 2002-11-19 09:37:08 by simonpj]

[ghc-hetmet.git] / ghc / compiler / specialise / Specialise.lhs

diff --git a/ghc/compiler/specialise/Specialise.lhs b/ghc/compiler/specialise/Specialise.lhs
index 746814f..ae61e15 100644 (file)
--- a/ghc/compiler/specialise/Specialise.lhs
+++ b/ghc/compiler/specialise/Specialise.lhs
@@ -9,9 +9,9 @@ module Specialise ( specProgram ) where
 #include "HsVersions.h"
 
 import CmdLineOpts     ( DynFlags, DynFlag(..) )
-import Id              ( Id, idName, idType, mkUserLocal, idSpecialisation, isDataConWrapId )
+import Id              ( Id, idName, idType, mkUserLocal, isDataConWrapId )
 import TcType          ( Type, mkTyVarTy, tcSplitSigmaTy, 
-                         tyVarsOfTypes, tyVarsOfTheta, 
+                         tyVarsOfTypes, tyVarsOfTheta, isClassPred,
                          mkForAllTys, tcCmpType
                        )
 import Subst           ( Subst, mkSubst, substTy, mkSubst, extendSubstList, mkInScopeSet,
@@ -25,8 +25,8 @@ import VarEnv
 import CoreSyn
 import CoreUtils       ( applyTypeToArgs )
 import CoreFVs         ( exprFreeVars, exprsFreeVars )
+import CoreTidy                ( pprTidyIdRules )
 import CoreLint                ( showPass, endPass )
-import PprCore         ( pprCoreRules )
 import Rules           ( addIdSpecialisations, lookupRule )
 
 import UniqSupply      ( UniqSupply,
@@ -41,9 +41,9 @@ import BasicTypes     ( Activation( AlwaysActive ) )
 import Bag
 import List            ( partition )
 import Util            ( zipEqual, zipWithEqual, cmpList, lengthIs,
-                         equalLength, lengthAtLeast )
+                         equalLength, lengthAtLeast, notNull )
 import Outputable
-
+import FastString
 
 infixr 9 `thenSM`
 \end{code}
@@ -586,7 +586,7 @@ specProgram dflags us binds
        endPass dflags "Specialise" Opt_D_dump_spec binds'
 
        dumpIfSet_dyn dflags Opt_D_dump_rules "Top-level specialisations"
-                 (vcat (map dump_specs (concat (map bindersOf binds'))))
+                 (vcat (map pprTidyIdRules (concat (map bindersOf binds'))))
 
        return binds'
   where
@@ -601,8 +601,6 @@ specProgram dflags us binds
     go (bind:binds) = go binds                                 `thenSM` \ (binds', uds) ->
                      specBind top_subst bind uds       `thenSM` \ (bind', uds') ->
                      returnSM (bind' ++ binds', uds')
-
-dump_specs var = pprCoreRules var (idSpecialisation var)
 \end{code}
 
 %************************************************************************
@@ -788,7 +786,7 @@ specDefn subst calls (fn, rhs)
        -- The first case is the interesting one
   |  rhs_tyvars `lengthIs` n_tyvars    -- Rhs of fn's defn has right number of big lambdas
   && rhs_bndrs  `lengthAtLeast` n_dicts        -- and enough dict args
-  && not (null calls_for_me)           -- And there are some calls to specialise
+  && notNull calls_for_me              -- And there are some calls to specialise
   && not (isDataConWrapId fn)          -- And it's not a data con wrapper, which have
                                        -- stupid overloading that simply discard the dictionary
 
@@ -889,7 +887,7 @@ specDefn subst calls (fn, rhs)
        let
                -- The rule to put in the function's specialisation is:
                --      forall b,d, d1',d2'.  f t1 b t3 d d1' d2' = f1 b d  
-           spec_env_rule = Rule (_PK_ ("SPEC " ++ showSDoc (ppr fn)))
+           spec_env_rule = Rule (mkFastString ("SPEC " ++ showSDoc (ppr fn)))
                                AlwaysActive
                                (poly_tyvars ++ rhs_dicts')
                                inst_args 
@@ -1005,6 +1003,10 @@ callDetailsToList calls = [ (id,tys,dicts)
 
 mkCallUDs subst f args 
   | null theta
+  || not (all isClassPred theta)       
+       -- Only specialise if all overloading is on class params. 
+       -- In ptic, with implicit params, the type args
+       -- *don't* say what the value of the implicit param is!
   || not (spec_tys `lengthIs` n_tyvars)
   || not ( dicts   `lengthIs` n_dicts)
   || maybeToBool (lookupRule (\act -> True) (substInScope subst) f args)
@@ -1027,10 +1029,9 @@ mkCallUDs subst f args
     spec_tys = [mk_spec_ty tv ty | (tv, Type ty) <- tyvars `zip` args]
     dicts    = [dict_expr | (_, dict_expr) <- theta `zip` (drop n_tyvars args)]
     
-    mk_spec_ty tyvar ty | tyvar `elemVarSet` constrained_tyvars
-                       = Just ty
-                       | otherwise
-                       = Nothing
+    mk_spec_ty tyvar ty 
+       | tyvar `elemVarSet` constrained_tyvars = Just ty
+       | otherwise                             = Nothing
 
 ------------------------------------------------------------                   
 plusUDs :: UsageDetails -> UsageDetails -> UsageDetails