+
%
% (c) The University of Glasgow 2006
% (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
A ``lint'' pass to check for Core correctness
\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 CoreLint (
lintCoreBindings,
lintUnfolding,
- showPass, endPass
+ showPass, endPass, endPassIf, endIteration
) where
#include "HsVersions.h"
import TyCon
import BasicTypes
import StaticFlags
+import ListSetOps
import DynFlags
import Outputable
import Util
\begin{code}
endPass :: DynFlags -> String -> DynFlag -> [CoreBind] -> IO [CoreBind]
-endPass dflags pass_name dump_flag binds
+endPass = dumpAndLint dumpIfSet_core
+
+endPassIf :: Bool -> DynFlags -> String -> DynFlag -> [CoreBind] -> IO [CoreBind]
+endPassIf cond = dumpAndLint (dumpIf_core cond)
+
+endIteration :: DynFlags -> String -> DynFlag -> [CoreBind] -> IO [CoreBind]
+endIteration = dumpAndLint dumpIfSet_dyn
+
+dumpAndLint :: (DynFlags -> DynFlag -> String -> SDoc -> IO ())
+ -> DynFlags -> String -> DynFlag -> [CoreBind] -> IO [CoreBind]
+dumpAndLint dump dflags pass_name dump_flag binds
= do
-- Report result size if required
-- This has the side effect of forcing the intermediate to be evaluated
(text " Result size =" <+> int (coreBindsSize binds))
-- Report verbosely, if required
- dumpIfSet_core dflags dump_flag pass_name (pprCoreBindings binds)
+ dump dflags dump_flag pass_name (pprCoreBindings binds)
-- Type check
lintCoreBindings dflags pass_name binds
\begin{code}
lintCoreBindings :: DynFlags -> String -> [CoreBind] -> IO ()
-lintCoreBindings dflags whoDunnit binds
+lintCoreBindings dflags _whoDunnit _binds
| not (dopt Opt_DoCoreLinting dflags)
= return ()
-- Put all the top-level binders in scope at the start
-- This is because transformation rules can bring something
-- into use 'unexpectedly'
- lint_binds binds = addInScopeVars (bindersOfBinds binds) $
+ lint_binds binds = addLoc TopLevelBindings $
+ addInScopeVars (bindersOfBinds binds) $
mapM lint_bind binds
lint_bind (Rec prs) = mapM_ (lintSingleBinding TopLevel Recursive) prs
Check a core binding, returning the list of variables bound.
\begin{code}
+lintSingleBinding :: TopLevelFlag -> RecFlag -> (Id, CoreExpr) -> LintM ()
lintSingleBinding top_lvl_flag rec_flag (binder,rhs)
= addLoc (RhsOf binder) $
-- Check the rhs
; checkTys from_ty expr_ty (mkCastErr from_ty expr_ty)
; return to_ty }
-lintCoreExpr (Note other_note expr)
+lintCoreExpr (Note _ expr)
= lintCoreExpr expr
lintCoreExpr (Let (NonRec bndr rhs) body)
else lintAndScopeId var
; scope $ \_ ->
do { -- Check the alternatives
- checkCaseAlts e scrut_ty alts
- ; mapM (lintCoreAlt scrut_ty alt_ty) alts
+ mapM (lintCoreAlt scrut_ty alt_ty) alts
+ ; checkCaseAlts e scrut_ty alts
; return alt_ty } }
where
pass_var f = f var
-lintCoreExpr e@(Type ty)
+lintCoreExpr e@(Type _)
= addErrL (mkStrangeTyMsg e)
\end{code}
do { res <- lintCoreArg ty a
; lintCoreArgs res args }
-lintCoreArg fun_ty a@(Type arg_ty) =
+lintCoreArg fun_ty (Type arg_ty) =
do { arg_ty <- lintTy arg_ty
; lintTyApp fun_ty arg_ty }
; checkKinds tyvar arg_ty
; return (substTyWith [tyvar] [arg_ty] body) }
+checkKinds :: Var -> Type -> LintM ()
checkKinds tyvar arg_ty
-- Arg type might be boxed for a function with an uncommitted
-- tyvar; notably this is used so that we can give
-- the simplifer correctly eliminates case that can't
-- possibly match.
-checkCaseAlts e ty []
+checkCaseAlts e _ []
= addErrL (mkNullAltsMsg e)
checkCaseAlts e ty alts =
-- Check that successive alternatives have increasing tags
increasing_tag (alt1 : rest@( alt2 : _)) = alt1 `ltAlt` alt2 && increasing_tag rest
- increasing_tag other = True
+ increasing_tag _ = True
non_deflt (DEFAULT, _, _) = False
- non_deflt alt = True
+ non_deflt _ = True
is_infinite_ty = case splitTyConApp_maybe ty of
- Nothing -> False
- Just (tycon, tycon_arg_tys) -> isPrimTyCon tycon
+ Nothing -> False
+ Just (tycon, _) -> isPrimTyCon tycon
\end{code}
\begin{code}
-> CoreAlt
-> LintM ()
-lintCoreAlt scrut_ty alt_ty alt@(DEFAULT, args, rhs) =
+lintCoreAlt _ alt_ty (DEFAULT, args, rhs) =
do { checkL (null args) (mkDefaultArgsMsg args)
; checkAltExpr rhs alt_ty }
-lintCoreAlt scrut_ty alt_ty alt@(LitAlt lit, args, rhs) =
+lintCoreAlt scrut_ty alt_ty (LitAlt lit, args, rhs) =
do { checkL (null args) (mkDefaultArgsMsg args)
; checkTys lit_ty scrut_ty (mkBadPatMsg lit_ty scrut_ty)
; checkAltExpr rhs alt_ty }
{ -- Check the pattern
-- Scrutinee type must be a tycon applicn; checked by caller
-- This code is remarkably compact considering what it does!
- -- NB: args must be in scope here so that the lintCoreArgs line works.
- -- NB: relies on existential type args coming *after* ordinary type args
-
+ -- NB: args must be in scope here so that the lintCoreArgs
+ -- line works.
+ -- NB: relies on existential type args coming *after*
+ -- ordinary type args
; con_result_ty <- lintCoreArgs con_payload_ty (varsToCoreExprs args)
; checkTys con_result_ty scrut_ty (mkBadPatMsg con_result_ty scrut_ty)
}
-}
instance Monad LintM where
- return x = LintM (\ loc subst errs -> (Just x, errs))
+ return x = LintM (\ _ _ errs -> (Just x, errs))
fail err = LintM (\ loc subst errs -> (Nothing, addErr subst errs (text err) loc))
m >>= k = LintM (\ loc subst errs ->
let (res, errs') = unLintM m loc subst errs in
| CasePat CoreAlt -- *Pattern* of the case alternative
| AnExpr CoreExpr -- Some expression
| ImportedUnfolding SrcLoc -- Some imported unfolding (ToDo: say which)
+ | TopLevelBindings
\end{code}
\begin{code}
checkL :: Bool -> Message -> LintM ()
-checkL True msg = return ()
+checkL True _ = return ()
checkL False msg = addErrL msg
addErrL :: Message -> LintM a
LintM (\ loc subst errs -> unLintM m (extra_loc:loc) subst errs)
addInScopeVars :: [Var] -> LintM a -> LintM a
-addInScopeVars vars m =
- LintM (\ loc subst errs -> unLintM m loc (extendTvInScope subst vars) errs)
+addInScopeVars vars m
+ | null dups
+ = LintM (\ loc subst errs -> unLintM m loc (extendTvInScope subst vars) errs)
+ | otherwise
+ = addErrL (dupVars dups)
+ where
+ (_, dups) = removeDups compare vars
updateTvSubst :: TvSubst -> LintM a -> LintM a
updateTvSubst subst' m =
- LintM (\ loc subst errs -> unLintM m loc subst' errs)
+ LintM (\ loc _ errs -> unLintM m loc subst' errs)
getTvSubst :: LintM TvSubst
-getTvSubst = LintM (\ loc subst errs -> (Just subst, errs))
+getTvSubst = LintM (\ _ subst errs -> (Just subst, errs))
applySubst :: Type -> LintM Type
applySubst ty = do { subst <- getTvSubst; return (substTy subst ty) }
%************************************************************************
\begin{code}
+dumpLoc :: LintLocInfo -> (SrcLoc, SDoc)
+
dumpLoc (RhsOf v)
= (getSrcLoc v, brackets (ptext SLIT("RHS of") <+> pp_binders [v]))
dumpLoc (AnExpr e)
= (noSrcLoc, text "In the expression:" <+> ppr e)
-dumpLoc (CaseAlt (con, args, rhs))
+dumpLoc (CaseAlt (con, args, _))
= (noSrcLoc, text "In a case alternative:" <+> parens (ppr con <+> pp_binders args))
-dumpLoc (CasePat (con, args, rhs))
+dumpLoc (CasePat (con, args, _))
= (noSrcLoc, text "In the pattern of a case alternative:" <+> parens (ppr con <+> pp_binders args))
dumpLoc (ImportedUnfolding locn)
= (locn, brackets (ptext SLIT("in an imported unfolding")))
+dumpLoc TopLevelBindings
+ = (noSrcLoc, empty)
pp_binders :: [Var] -> SDoc
pp_binders bs = sep (punctuate comma (map pp_binder bs))
pp_binder :: Var -> SDoc
pp_binder b | isId b = hsep [ppr b, dcolon, ppr (idType b)]
- | isTyVar b = hsep [ppr b, dcolon, ppr (tyVarKind b)]
+ | otherwise = hsep [ppr b, dcolon, ppr (tyVarKind b)]
\end{code}
\begin{code}
text "Scrutinee type:" <+> ppr scrut_ty,
hsep [ptext SLIT("Current TV subst"), ppr subst]]
+mkNonDefltMsg, mkNonIncreasingAltsMsg :: CoreExpr -> Message
mkNonDefltMsg e
= hang (text "Case expression with DEFAULT not at the beginnning") 4 (ppr e)
mkNonIncreasingAltsMsg e
hsep [ptext SLIT("Rhs type:"), ppr ty]]
mkRhsPrimMsg :: Id -> CoreExpr -> Message
-mkRhsPrimMsg binder rhs
+mkRhsPrimMsg binder _rhs
= vcat [hsep [ptext SLIT("The type of this binder is primitive:"),
ppr binder],
hsep [ptext SLIT("Binder's type:"), ppr (idType binder)]
= vcat [hsep [ptext SLIT("A variable has unboxed tuple type:"), ppr binder],
hsep [ptext SLIT("Binder's type:"), ppr (idType binder)]]
+mkCastErr :: Type -> Type -> Message
mkCastErr from_ty expr_ty
= vcat [ptext SLIT("From-type of Cast differs from type of enclosed expression"),
ptext SLIT("From-type:") <+> ppr from_ty,
ptext SLIT("Type of enclosed expr:") <+> ppr expr_ty
]
+dupVars :: [[Var]] -> Message
+dupVars vars
+ = hang (ptext SLIT("Duplicate variables brought into scope"))
+ 2 (ppr vars)
+
+mkStrangeTyMsg :: CoreExpr -> Message
mkStrangeTyMsg e
= ptext SLIT("Type where expression expected:") <+> ppr e
\end{code}