Generalise the types of mk_FunBind, mk_easy_FunBind, mkVarBind

[ghc-hetmet.git] / compiler / main / TidyPgm.lhs

diff --git a/compiler/main/TidyPgm.lhs b/compiler/main/TidyPgm.lhs
index 6b89b33..a1a049a 100644 (file)
--- a/compiler/main/TidyPgm.lhs
+++ b/compiler/main/TidyPgm.lhs
@@ -4,6 +4,13 @@
 \section{Tidying up Core}
 
 \begin{code}
+{-# OPTIONS -w #-}
+-- The above warning supression flag is a temporary kludge.
+-- While working on this module you are encouraged to remove it and fix
+-- any warnings in the module. See
+--     http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
+-- for details
+
 module TidyPgm( mkBootModDetails, tidyProgram ) where
 
 #include "HsVersions.h"
@@ -28,11 +35,8 @@ import IdInfo                {- loads of stuff -}
 import InstEnv         ( Instance, DFunId, instanceDFunId, setInstanceDFunId )
 import NewDemand       ( isBottomingSig, topSig )
 import BasicTypes      ( Arity, isNeverActive, isNonRuleLoopBreaker )
-import Name            ( Name, getOccName, nameOccName, mkInternalName,
-                         localiseName, isExternalName, nameSrcLoc,
-                         isWiredInName, getName
-                       )
-import NameSet         ( NameSet, elemNameSet, filterNameSet )
+import Name
+import NameSet         ( NameSet, elemNameSet )
 import IfaceEnv                ( allocateGlobalBinder )
 import NameEnv         ( filterNameEnv, mapNameEnv )
 import OccName         ( TidyOccEnv, initTidyOccEnv, tidyOccName )
@@ -43,11 +47,10 @@ import TyCon                ( TyCon, makeTyConAbstract, tyConDataCons, isNewTyCon,
                          newTyConRep, tyConSelIds, isAlgTyCon,
                          isEnumerationTyCon, isOpenTyCon )
 import Class           ( classSelIds )
-import Module          ( Module )
+import Module
 import HscTypes
 import Maybes          ( orElse, mapCatMaybes )
 import ErrUtils                ( showPass, dumpIfSet_core )
-import PackageConfig   ( PackageId )
 import UniqSupply      ( splitUniqSupply, uniqFromSupply )
 import Outputable
 import FastTypes  hiding ( fastOr )
@@ -141,7 +144,6 @@ mkBootModDetails hsc_env (ModGuts { mg_module    = mod
                             , md_fam_insts = fam_insts
                             , md_rules     = []
                             , md_exports   = exports
-                             , md_modBreaks = modBreaks 
                              , md_vect_info = noVectInfo
                              })
        }
@@ -287,12 +289,6 @@ tidyProgram hsc_env
              ; implicit_binds = getImplicitBinds type_env
              ; all_tidy_binds = implicit_binds ++ tidy_binds
              ; alg_tycons = filter isAlgTyCon (typeEnvTyCons type_env)
-
-              ; tidy_vect_info = VectInfo 
-                                   (filterNameSet (isElemId type_env) 
-                                                  (vectInfoCCVar vect_info))
-                -- filter against `type_env', not `tidy_type_env', as we must
-                -- keep all implicit names
              }
 
        ; endPass dflags "Tidy Core" Opt_D_dump_simpl all_tidy_binds
@@ -306,15 +302,15 @@ tidyProgram hsc_env
                           cg_dir_imps = dir_imps,
                           cg_foreign  = foreign_stubs,
                           cg_dep_pkgs = dep_pkgs deps,
-                          cg_hpc_info = hpc_info }, 
+                          cg_hpc_info = hpc_info,
+                           cg_modBreaks = modBreaks }, 
 
                   ModDetails { md_types     = tidy_type_env,
                                md_rules     = tidy_rules,
                                md_insts     = tidy_insts,
                                md_fam_insts = fam_insts,
                                md_exports   = exports,
-                                md_modBreaks = modBreaks,
-                                md_vect_info = tidy_vect_info
+                                md_vect_info = vect_info    -- is already tidy
                               })
        }
 
@@ -323,11 +319,6 @@ lookup_dfun type_env dfun_id
        Just (AnId dfun_id') -> dfun_id'
        other -> pprPanic "lookup_dfun" (ppr dfun_id)
 
-isElemId type_env name
-  = case lookupTypeEnv type_env name of
-       Just (AnId _) -> True
-       _             -> False
-
 tidyTypeEnv :: Bool -> NameSet -> TypeEnv -> [CoreBind] -> TypeEnv
 
 -- The competed type environment is gotten from
@@ -685,7 +676,7 @@ tidyTopName mod nc_var ext_ids occ_env id
     global     = isExternalName name
     local      = not global
     internal   = not external
-    loc                = nameSrcLoc name
+    loc                = nameSrcSpan name
 
     (occ_env', occ') = tidyOccName occ_env (nameOccName name)
 
@@ -726,9 +717,10 @@ tidyTopPair ext_ids rhs_tidy_env caf_info name' (bndr, rhs)
     bndr'   = mkVanillaGlobal name' ty' idinfo'
     ty'            = tidyTopType (idType bndr)
     rhs'    = tidyExpr rhs_tidy_env rhs
+    idinfo  = idInfo bndr
     idinfo' = tidyTopIdInfo rhs_tidy_env (isJust maybe_external)
-                           (idInfo bndr) unfold_info arity
-                           caf_info
+                           idinfo unfold_info worker_info
+                           arity caf_info
 
     -- Expose an unfolding if ext_ids tells us to
     -- Remember that ext_ids maps an Id to a Bool: 
@@ -737,6 +729,7 @@ tidyTopPair ext_ids rhs_tidy_env caf_info name' (bndr, rhs)
     show_unfold = maybe_external `orElse` False
     unfold_info | show_unfold = mkTopUnfolding rhs'
                | otherwise   = noUnfolding
+    worker_info = tidyWorker rhs_tidy_env show_unfold (workerInfo idinfo)
 
     -- Usually the Id will have an accurate arity on it, because
     -- the simplifier has just run, but not always. 
@@ -760,7 +753,7 @@ tidyTopPair ext_ids rhs_tidy_env caf_info name' (bndr, rhs)
 --     unfoldings, which are inside Ids imported by GHCi. Ditto RULES.
 --     CoreToStg makes use of this when constructing SRTs.
 
-tidyTopIdInfo tidy_env is_external idinfo unfold_info arity caf_info
+tidyTopIdInfo tidy_env is_external idinfo unfold_info worker_info arity caf_info
   | not is_external    -- For internal Ids (not externally visible)
   = vanillaIdInfo      -- we only need enough info for code generation
                        -- Arity and strictness info are enough;
@@ -776,17 +769,27 @@ tidyTopIdInfo tidy_env is_external idinfo unfold_info arity caf_info
        `setAllStrictnessInfo` newStrictnessInfo idinfo
        `setInlinePragInfo`    inlinePragInfo idinfo
        `setUnfoldingInfo`     unfold_info
-       `setWorkerInfo`        tidyWorker tidy_env (workerInfo idinfo)
+       `setWorkerInfo`        worker_info
                -- NB: we throw away the Rules
                -- They have already been extracted by findExternalRules
 
 
 
 ------------  Worker  --------------
-tidyWorker tidy_env (HasWorker work_id wrap_arity) 
-  = HasWorker (tidyVarOcc tidy_env work_id) wrap_arity
-tidyWorker tidy_env other
+tidyWorker tidy_env show_unfold NoWorker
   = NoWorker
+tidyWorker tidy_env show_unfold (HasWorker work_id wrap_arity) 
+  | show_unfold = HasWorker (tidyVarOcc tidy_env work_id) wrap_arity
+  | otherwise   = WARN( True, ppr work_id ) NoWorker
+    -- NB: do *not* expose the worker if show_unfold is off,
+    --     because that means this thing is a loop breaker or
+    --     marked NOINLINE or something like that
+    -- This is important: if you expose the worker for a loop-breaker
+    -- then you can make the simplifier go into an infinite loop, because
+    -- in effect the unfolding is exposed.  See Trac #1709
+    -- 
+    -- Mind you, it probably should not be w/w'd in the first place; 
+    -- hence the WARN
 \end{code}
 
 %************************************************************************