Make sure DEFAULT always comes first in generated PA dictionaries

[ghc-hetmet.git] / compiler / vectorise / VectType.hs

diff --git a/compiler/vectorise/VectType.hs b/compiler/vectorise/VectType.hs
index 08a8067..9d9db53 100644 (file)
--- a/compiler/vectorise/VectType.hs
+++ b/compiler/vectorise/VectType.hs
@@ -1,4 +1,5 @@
-module VectType ( vectTyCon, vectType, vectTypeEnv )
+module VectType ( vectTyCon, vectType, vectTypeEnv,
+                   PAInstance, painstInstance, buildPADict )
 where
 
 #include "HsVersions.h"
@@ -8,18 +9,20 @@ import VectUtils
 
 import HscTypes          ( TypeEnv, extendTypeEnvList, typeEnvTyCons )
 import CoreSyn
+import CoreUtils
 import DataCon
 import TyCon
 import Type
 import TypeRep
 import Coercion
 import FamInstEnv        ( FamInst, mkLocalFamInst )
-import InstEnv           ( Instance )
+import InstEnv           ( Instance, mkLocalInstance, instanceDFunId )
 import OccName
 import MkId
-import BasicTypes        ( StrictnessMark(..), boolToRecFlag )
+import BasicTypes        ( StrictnessMark(..), OverlapFlag(..), boolToRecFlag )
+import Var               ( Var )
 import Id                ( mkWildId )
-import Name              ( Name )
+import Name              ( Name, getOccName )
 import NameEnv
 import TysWiredIn        ( intTy, intDataCon )
 import TysPrim           ( intPrimTy )
@@ -72,7 +75,13 @@ vectType ty = pprPanic "vectType:" (ppr ty)
 
 type TyConGroup = ([TyCon], UniqSet TyCon)
 
-vectTypeEnv :: TypeEnv -> VM (TypeEnv, [FamInst], [Instance])
+data PAInstance = PAInstance {
+                    painstInstance  :: Instance
+                  , painstVectTyCon :: TyCon
+                  , painstArrTyCon  :: TyCon
+                  }
+
+vectTypeEnv :: TypeEnv -> VM (TypeEnv, [FamInst], [PAInstance])
 vectTypeEnv env
   = do
       cs <- readGEnv $ mk_map . global_tycons
@@ -80,17 +89,22 @@ vectTypeEnv env
           keep_dcs             = concatMap tyConDataCons keep_tcs
       zipWithM_ defTyCon   keep_tcs keep_tcs
       zipWithM_ defDataCon keep_dcs keep_dcs
-      vect_tcs <- vectTyConDecls conv_tcs
-      parr_tcs1 <- zipWithM buildPArrayTyCon keep_tcs keep_tcs
-      parr_tcs2 <- zipWithM buildPArrayTyCon conv_tcs vect_tcs
-      let new_tcs = vect_tcs ++ parr_tcs1 ++ parr_tcs2
+      new_tcs <- vectTyConDecls conv_tcs
+
+      let orig_tcs = keep_tcs ++ conv_tcs
+          vect_tcs  = keep_tcs ++ new_tcs
+
+      parr_tcs <- zipWithM buildPArrayTyCon orig_tcs vect_tcs
+      pa_insts <- zipWithM buildPAInstance  vect_tcs parr_tcs
+      
+      let all_new_tcs = new_tcs ++ parr_tcs
 
       let new_env = extendTypeEnvList env
-                       (map ATyCon new_tcs
-                        ++ [ADataCon dc | tc <- new_tcs
+                       (map ATyCon all_new_tcs
+                        ++ [ADataCon dc | tc <- all_new_tcs
                                         , dc <- tyConDataCons tc])
 
-      return (new_env, map mkLocalFamInst (parr_tcs1 ++ parr_tcs2), [])
+      return (new_env, map mkLocalFamInst parr_tcs, pa_insts)
   where
     tycons = typeEnvTyCons env
     groups = tyConGroups tycons
@@ -253,21 +267,71 @@ buildPArrayDataCon orig_name vect_tc repr_tc
     types = [ty | dc <- tyConDataCons vect_tc
                 , ty <- dataConRepArgTys dc]
 
-buildLengthPA :: TyCon -> VM CoreExpr
-buildLengthPA repr_tc
+buildPAInstance :: TyCon -> TyCon -> VM PAInstance
+buildPAInstance vect_tc arr_tc
   = do
-      arg   <- newLocalVar FSLIT("xs") arg_ty
+      pa <- builtin paClass
+      let inst_ty = mkForAllTys tvs
+                  . (mkFunTys $ mkPredTys [ClassP pa [ty] | ty <- arg_tys])
+                  $ mkPredTy (ClassP pa [mkTyConApp vect_tc arg_tys])
+
+      dfun <- newExportedVar (mkPADFunOcc $ getOccName vect_tc) inst_ty
+
+      return $ PAInstance {
+                 painstInstance  = mkLocalInstance dfun NoOverlap
+               , painstVectTyCon = vect_tc
+               , painstArrTyCon  = arr_tc
+               }
+  where
+    tvs = tyConTyVars arr_tc
+    arg_tys = mkTyVarTys tvs
+
+buildPADict :: PAInstance -> VM [(Var, CoreExpr)]
+buildPADict (PAInstance {
+               painstInstance  = inst
+             , painstVectTyCon = vect_tc
+             , painstArrTyCon  = arr_tc })
+  = localV . abstractOverTyVars (tyConTyVars arr_tc) $ \abstract ->
+    do
+      meth_binds <- mapM mk_method paMethods
+      let meth_exprs = map (Var . fst) meth_binds
+
+      pa_dc <- builtin paDictDataCon
+      let dict = mkConApp pa_dc (Type (mkTyConApp vect_tc arg_tys) : meth_exprs)
+          body = Let (Rec meth_binds) dict
+      return [(instanceDFunId inst, abstract body)]
+  where
+    tvs = tyConTyVars arr_tc
+    arg_tys = mkTyVarTys tvs
+
+    mk_method (name, build)
+      = localV
+      $ do
+          body <- build vect_tc arr_tc
+          var  <- newLocalVar name (exprType body)
+          return (var, mkInlineMe body)
+          
+paMethods = [(FSLIT("lengthPA"),    buildLengthPA),
+             (FSLIT("replicatePA"), buildReplicatePA)]
+
+buildLengthPA :: TyCon -> TyCon -> VM CoreExpr
+buildLengthPA vect_tc arr_tc
+  = do
+      parr_ty <- mkPArrayType (mkTyConApp vect_tc arg_tys)
+      arg <- newLocalVar FSLIT("xs") parr_ty
+      let scrut    = unwrapFamInstScrut arr_tc arg_tys (Var arg)
+          scrut_ty = exprType scrut
       shape <- newLocalVar FSLIT("sel") shape_ty
       body  <- lengthPA (Var shape)
+      wilds <- mapM newDummyVar repr_tys
       return . Lam arg
-             $ Case (Var arg) (mkWildId arg_ty) intPrimTy
-                    [(DataAlt repr_dc, shape : map mkWildId repr_tys, body)]
+             $ Case scrut (mkWildId scrut_ty) intPrimTy
+                    [(DataAlt repr_dc, shape : wilds, body)]
   where
-    arg_ty = mkTyConApp repr_tc . mkTyVarTys $ tyConTyVars repr_tc
-    [repr_dc] = tyConDataCons repr_tc
+    arg_tys = mkTyVarTys $ tyConTyVars arr_tc
+    [repr_dc] = tyConDataCons arr_tc
     shape_ty : repr_tys = dataConRepArgTys repr_dc
 
-
 -- data T = C0 t1 ... tm
 --          ...
 --          Ck u1 ... un
@@ -334,7 +398,7 @@ buildReplicatePA vect_tc arr_tc
           arr_ty <- mkPArrayType ty
 
           return $ Case val wild arr_ty
-                     [(DataAlt dc, pre ++ (var : post), rep), (DEFAULT, [], empty)]
+                     [(DEFAULT, [], empty), (DataAlt dc, pre ++ (var : post), rep)]
 
 -- | Split the given tycons into two sets depending on whether they have to be
 -- converted (first list) or not (second list). The first argument contains