do flattening before simpleOptPgm so evaluation "order" is not lost

diff --git a/compiler/deSugar/Desugar.lhs b/compiler/deSugar/Desugar.lhs
index 10858f8..374c13b 100644 (file)
--- a/compiler/deSugar/Desugar.lhs
+++ b/compiler/deSugar/Desugar.lhs
@@ -43,6 +43,10 @@ import Data.List
 import Data.IORef
 import PrelNames
 import UniqSupply
+import UniqFM
+import CoreFVs
+import Type
+import Coercion
 \end{code}
 
 %************************************************************************
@@ -52,6 +56,7 @@ import UniqSupply
 %************************************************************************
 
 \begin{code}
+
 -- | Main entry point to the desugarer.
 deSugar :: HscEnv -> ModLocation -> TcGblEnv -> IO (Messages, Maybe ModGuts)
 -- Can modify PCS by faulting in more declarations
@@ -229,7 +234,7 @@ deSugar hsc_env
               final_prs = addExportFlagsAndRules target
                              export_set keep_alive rules_for_locals (fromOL all_prs)
 
-              final_pgm = combineEvBinds ds_ev_binds final_prs
+              final_pgm = simplifyBinds $ combineEvBinds ds_ev_binds final_prs
        -- Notice that we put the whole lot in a big Rec, even the foreign binds
        -- When compiling PrelFloat, which defines data Float = F# Float#
        -- we want F# to be in scope in the foreign marshalling code!
@@ -241,11 +246,7 @@ deSugar hsc_env
                (vcat [ pprCoreBindings final_pgm
                      , pprRules rules_for_imps ])
 
-       ; (ds_binds, ds_rules_for_imps) <- simpleOptPgm dflags final_pgm rules_for_imps
-                        -- The simpleOptPgm gets rid of type 
-                        -- bindings plus any stupid dead code
-
-        ; ds_binds' <- if dopt Opt_F_coqpass dflags
+        ; ds_binds <- if dopt Opt_F_coqpass dflags
                        then do { us <- mkSplitUniqSupply '~'
                                ; return (coqPassCoreToCore
                                              hetmet_brak
@@ -254,7 +255,7 @@ deSugar hsc_env
                                              hetmet_unflatten
                                              hetmet_flattened_id
                                              us
-                                             ds_binds
+                                             final_pgm
                                              hetmet_PGArrow
                                              hetmet_PGArrow_unit
                                              hetmet_PGArrow_tensor
@@ -277,7 +278,11 @@ deSugar hsc_env
                                              hetmet_pga_curryl
                                              hetmet_pga_curryr)
                                }
-                       else return ds_binds
+                       else return final_pgm
+
+       ; (ds_binds', ds_rules_for_imps) <- simpleOptPgm dflags ds_binds rules_for_imps
+                        -- The simpleOptPgm gets rid of type 
+                        -- bindings plus any stupid dead code
 
         ; dumpIfSet_dyn dflags Opt_D_coqpass "Coq Pass Output" $ text $ coqPassCoreToString ds_binds'
 
@@ -546,3 +551,35 @@ dsVect (L loc (HsVect v rhs))
 --        ; return $ Vect v (Just rhs')
 --       }
 \end{code}
+
+
+
+\begin{code}
+--
+-- Simplification routines run before the flattener.  We can't use
+-- simpleOptPgm -- it doesn't preserve the order of subexpressions or
+-- let-binding groups.
+--
+simplify :: Expr CoreBndr -> Expr CoreBndr
+simplify (Var v)                 = Var v
+simplify (App e1 e2)             = App (simplify e1) (simplify e2)
+simplify (Lit lit)               = Lit lit
+simplify (Note note e)           = Note note (simplify e)
+simplify (Cast e co)             = if tcEqType (fst $ coercionKind co) (snd $ coercionKind co)
+                                       then simplify e
+                                       else Cast (simplify e) co
+simplify (Lam v e)               = Lam v (simplify e)
+simplify (Type t)                = Type t
+simplify (Case e b ty as)        = Case (simplify e) b ty (map (\(a,b,e) -> (a,b,simplify e)) as)
+simplify (Let bind body)         = foldr Let (simplify body) (simplifyBind bind)
+
+simplifyBind :: Bind CoreBndr -> [Bind CoreBndr]
+simplifyBind (NonRec b e)             = [NonRec b (simplify e)]
+simplifyBind (Rec [])                 = []
+simplifyBind (Rec (rbs@((b,e):rbs'))) =
+    if or $ map (\x -> elemUFM x (exprFreeIds e)) (map fst rbs)
+    then [Rec (map (\(v,e) -> (v,simplify e)) rbs)]
+    else (NonRec b (simplify e)):(simplifyBind $ Rec rbs')
+
+simplifyBinds = concatMap simplifyBind
+\end{code}
\ No newline at end of file

diff --git a/compiler/hetmet b/compiler/hetmet
index bebffa4..a45824c 160000 (submodule)
--- a/compiler/hetmet
+++ b/compiler/hetmet
@@ -1 +1 @@
-Subproject commit bebffa435dbc5afd126f6972fbf220977455854d
+Subproject commit a45824c7d03fcf797e22d2919187a7e97fb567cc

diff --git a/libraries/base b/libraries/base
index c13aea9..b64a0d3 160000 (submodule)
--- a/libraries/base
+++ b/libraries/base
@@ -1 +1 @@
-Subproject commit c13aea9521b5b8bafb7507e3761484bce17e44dd
+Subproject commit b64a0d3816bd3f2586a2544f99e9b42d9a24e7ee