liquidhaskell-0.1: Language/Haskell/Liquid/Constraint.hs
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE NoMonomorphismRestriction #-}
{-# LANGUAGE TypeSynonymInstances #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE TupleSections #-}
{-# LANGUAGE DeriveDataTypeable #-}
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE PatternGuards #-}
{-# LANGUAGE MultiParamTypeClasses #-}
-- | This module defines the representation of Subtyping and WF Constraints, and
-- the code for syntax-directed constraint generation.
module Language.Haskell.Liquid.Constraint (
-- * Constraint information output by generator
CGInfo (..)
-- * Function that does the actual generation
, generateConstraints
-- * Project Constraints to Fixpoint Format
, cgInfoFInfo , cgInfoFInfoBot, cgInfoFInfoKvars
-- * KVars in constraints, for debug purposes
-- , kvars, kvars'
) where
import CoreSyn
import SrcLoc
import Type -- (coreEqType)
import PrelNames
import qualified TyCon as TC
import TypeRep
import Class (Class, className)
import Var
import Id
import Name (getSrcSpan)
import Text.PrettyPrint.HughesPJ
import Control.Monad.State
import Control.Applicative ((<$>))
import Control.Exception.Base
import Data.Monoid (mconcat)
import Data.Maybe (fromJust, isJust, fromMaybe, catMaybes)
import qualified Data.HashMap.Strict as M
import qualified Data.HashSet as S
import qualified Data.List as L
import Data.Bifunctor
import Data.List (foldl')
import Text.Printf
import qualified Language.Haskell.Liquid.CTags as Tg
import qualified Language.Fixpoint.Types as F
import Language.Fixpoint.Names (dropModuleNames)
import Language.Fixpoint.Sort (pruneUnsortedReft)
import Language.Haskell.Liquid.Fresh
import Language.Haskell.Liquid.Types hiding (binds, Loc, loc, freeTyVars)
import Language.Haskell.Liquid.Bare
import Language.Haskell.Liquid.Annotate
import Language.Haskell.Liquid.GhcInterface
import Language.Haskell.Liquid.RefType
import Language.Haskell.Liquid.PredType hiding (freeTyVars)
import Language.Haskell.Liquid.Predicates
import Language.Haskell.Liquid.GhcMisc (isInternal, collectArguments, getSourcePos, pprDoc, tickSrcSpan, hasBaseTypeVar, showPpr)
import Language.Haskell.Liquid.Misc
import Language.Fixpoint.Misc
import Language.Haskell.Liquid.Qualifier
import Control.DeepSeq
-----------------------------------------------------------------------
------------- Constraint Generation: Toplevel -------------------------
-----------------------------------------------------------------------
generateConstraints :: GhcInfo -> CGInfo
generateConstraints info = {-# SCC "ConsGen" #-} execState act $ initCGI cfg info
where
act = consAct (info {cbs = fst pds}) (snd pds)
pds = generatePredicates info
cfg = config $ spec info
consAct info penv
= do γ <- initEnv info penv
foldM consCBTop γ (cbs info)
hcs <- hsCs <$> get
hws <- hsWfs <$> get
fcs <- concat <$> mapM splitC hcs
fws <- concat <$> mapM splitW hws
modify $ \st -> st { fixCs = fcs } { fixWfs = fws }
initEnv :: GhcInfo -> F.SEnv PrType -> CG CGEnv
initEnv info penv
= do let tce = tcEmbeds $ spec info
defaults <- forM (impVars info) $ \x -> liftM (x,) (trueTy $ varType x)
tyi <- tyConInfo <$> get
let f0 = grty info -- asserted refinements (for defined vars)
f0' <- grtyTop info -- default TOP reftype (for exported vars without spec)
let f1 = defaults -- default TOP reftype (for all vars)
f2 <- refreshArgs' $ assm info -- assumed refinements (for imported vars)
f3 <- refreshArgs' $ ctor' $ spec info -- constructor refinements (for measures)
let bs = (map (unifyts' tce tyi penv)) <$> [f0 ++ f0', f1, f2, f3]
lts <- lits <$> get
let tcb = mapSnd (rTypeSort tce ) <$> concat bs
let γ0 = measEnv (spec info) penv (head bs) (cbs info) (tcb ++ lts)
foldM (++=) γ0 [("initEnv", x, y) | (x, y) <- concat bs]
where refreshArgs' = mapM (mapSndM refreshArgs)
-- where tce = tcEmbeds $ spec info
ctor' = map (mapSnd val) . ctor
unifyts' tce tyi penv = (second (addTyConInfo tce tyi)) . (unifyts penv)
unifyts penv (x, t) = (x', unify pt t)
where pt = F.lookupSEnv x' penv
x' = varSymbol x
measEnv sp penv xts cbs lts
= CGE { loc = noSrcSpan
, renv = fromListREnv $ second (uRType . val) <$> meas sp
, syenv = F.fromListSEnv $ freeSyms sp
, penv = penv
, fenv = initFEnv (lts ++ (second (rTypeSort tce . val) <$> meas sp))
, recs = S.empty
, invs = mkRTyConInv $ invariants sp
, grtys = fromListREnv xts
, emb = tce
, tgEnv = Tg.makeTagEnv cbs
, tgKey = Nothing
, trec = Nothing
, lcb = M.empty
}
where tce = tcEmbeds sp
assm = assm_grty impVars
grty = assm_grty defVars
assm_grty f info = [ (x, val t) | (x, t) <- sigs, x `S.member` xs ]
where
xs = S.fromList $ f info
sigs = tySigs $ spec info
grtyTop info = forM topVs $ \v -> (v,) <$> (trueTy $ varType v) -- val $ varSpecType v) | v <- defVars info, isTop v]
where
topVs = filter isTop $ defVars info
isTop v = isExportedId v && not (v `S.member` useVs) && not (v `S.member` sigVs)
useVs = S.fromList $ useVars info
sigVs = S.fromList $ [v | (v,_) <- tySigs $ spec info]
------------------------------------------------------------------------
-- | Helpers: Reading/Extending Environment Bindings -------------------
------------------------------------------------------------------------
data FEnv = FE { fe_binds :: !F.IBindEnv -- ^ Integer Keys for Fixpoint Environment
, fe_env :: !(F.SEnv F.Sort) -- ^ Fixpoint Environment
}
insertFEnv (FE benv env) ((x, t), i)
= FE (F.insertsIBindEnv [i] benv) (F.insertSEnv x t env)
insertsFEnv = L.foldl' insertFEnv
initFEnv init = FE F.emptyIBindEnv $ F.fromListSEnv (wiredSortedSyms ++ init)
data CGEnv
= CGE { loc :: !SrcSpan -- ^ Location in original source file
, renv :: !REnv -- ^ SpecTypes for Bindings in scope
, syenv :: !(F.SEnv Var) -- ^ Map from free Symbols (e.g. datacons) to Var
, penv :: !(F.SEnv PrType) -- ^ PrTypes for top-level bindings (merge with renv)
, fenv :: !FEnv -- ^ Fixpoint Environment
, recs :: !(S.HashSet Var) -- ^ recursive defs being processed (for annotations)
, invs :: !RTyConInv -- ^ Datatype invariants
, grtys :: !REnv -- ^ Top-level variables with (assert)-guarantees to verify
, emb :: F.TCEmb TC.TyCon -- ^ How to embed GHC Tycons into fixpoint sorts
, tgEnv :: !Tg.TagEnv -- ^ Map from top-level binders to fixpoint tag
, tgKey :: !(Maybe Tg.TagKey) -- ^ Current top-level binder
, trec :: !(Maybe (M.HashMap F.Symbol SpecType)) -- ^ Type of recursive function with decreasing constraints
, lcb :: !(M.HashMap F.Symbol CoreExpr) -- ^ Let binding that have not been checked
} -- deriving (Data, Typeable)
instance PPrint CGEnv where
pprint = pprint . renv
instance Show CGEnv where
show = showpp
getTag :: CGEnv -> F.Tag
getTag γ = maybe Tg.defaultTag (`Tg.getTag` (tgEnv γ)) (tgKey γ)
getPrType :: CGEnv -> F.Symbol -> Maybe PrType
getPrType γ x = F.lookupSEnv x (penv γ)
setLoc :: CGEnv -> SrcSpan -> CGEnv
γ `setLoc` src
| isGoodSrcSpan src = γ { loc = src }
| otherwise = γ
withRecs :: CGEnv -> [Var] -> CGEnv
withRecs γ xs = γ { recs = foldl' (flip S.insert) (recs γ) xs }
withTRec γ xts = γ' {trec = Just $ M.fromList xts' `M.union` trec'}
where γ' = γ `withRecs` (fst <$> xts)
trec' = fromMaybe M.empty $ trec γ
xts' = mapFst varSymbol <$> xts
setBind :: CGEnv -> Tg.TagKey -> CGEnv
setBind γ k
| Tg.memTagEnv k (tgEnv γ) = γ { tgKey = Just k }
| otherwise = γ
isGeneric :: RTyVar -> SpecType -> Bool
isGeneric α t = all (\(c, α') -> (α'/=α) || isOrd c || isEq c ) (classConstrs t)
where classConstrs t = [(c, α') | (c, ts) <- tyClasses t
, t' <- ts
, α' <- freeTyVars t']
isOrd = (ordClassName ==) . className
isEq = (eqClassName ==) . className
-- isBase :: RType a -> Bool
isBase (RAllP _ t) = isBase t
isBase (RVar _ _) = True
isBase (RApp _ ts _ _) = all isBase ts
isBase (RFun _ t1 t2 _) = isBase t1 && isBase t2
isBase _ = False
-----------------------------------------------------------------
------------------- Constraints: Types --------------------------
-----------------------------------------------------------------
data SubC = SubC { senv :: !CGEnv
, lhs :: !SpecType
, rhs :: !SpecType
}
data WfC = WfC !CGEnv !SpecType
-- deriving (Data, Typeable)
type FixSubC = F.SubC Cinfo
type FixWfC = F.WfC Cinfo
instance PPrint SubC where
pprint c = pprint (senv c)
$+$ ((text " |- ") <+> ( (pprint (lhs c))
$+$ text "<:"
$+$ (pprint (rhs c))))
instance PPrint WfC where
pprint (WfC w r) = pprint w <> text " |- " <> pprint r
------------------------------------------------------------
------------------- Constraint Splitting -------------------
------------------------------------------------------------
splitW :: WfC -> CG [FixWfC]
splitW (WfC γ t@(RFun x t1 t2 _))
= do ws <- bsplitW γ t
ws' <- splitW (WfC γ t1)
γ' <- (γ, "splitW") += (x, t1)
ws'' <- splitW (WfC γ' t2)
return $ ws ++ ws' ++ ws''
splitW (WfC γ t@(RAppTy t1 t2 _))
= do ws <- bsplitW γ t
ws' <- splitW (WfC γ t1)
ws'' <- splitW (WfC γ t2)
return $ ws ++ ws' ++ ws''
splitW (WfC γ (RAllT _ r))
= splitW (WfC γ r)
splitW (WfC γ (RAllP _ r))
= splitW (WfC γ r)
splitW (WfC γ t@(RVar _ _))
= bsplitW γ t
splitW (WfC _ (RCls _ _))
= return []
splitW (WfC γ t@(RApp _ ts rs _))
= do ws <- bsplitW γ t
γ' <- γ `extendEnvWithVV` t
ws' <- concat <$> mapM splitW (map (WfC γ') ts)
ws'' <- concat <$> mapM (rsplitW γ) rs
return $ ws ++ ws' ++ ws''
splitW (WfC _ t)
= errorstar $ "splitW cannot handle: " ++ showpp t
rsplitW _ (RMono _ _)
= errorstar "Constrains: rsplitW for RMono"
rsplitW γ (RPoly ss t0)
= do γ' <- foldM (++=) γ [("rsplitC", x, ofRSort s) | (x, s) <- ss]
splitW $ WfC γ' t0
bsplitW :: CGEnv -> SpecType -> CG [FixWfC]
bsplitW γ t = pruneRefs <$> get >>= return . bsplitW' γ t
bsplitW' γ t pflag
| F.isNonTrivialSortedReft r' = [F.wfC (fe_binds $ fenv γ) r' Nothing ci]
| otherwise = []
where
r' = rTypeSortedReft' pflag γ t
ci = Ci (loc γ) Nothing
mkSortedReft tce = F.RR . rTypeSort tce
------------------------------------------------------------
splitC :: SubC -> CG [FixSubC]
------------------------------------------------------------
splitC (SubC γ (REx x tx t1) (REx x2 _ t2)) | x == x2
= do γ' <- (γ, "addExBind 0") += (x, forallExprRefType γ tx)
splitC (SubC γ' t1 t2)
splitC (SubC γ t1 (REx x tx t2))
= do γ' <- (γ, "addExBind 1") += (x, forallExprRefType γ tx)
let xs = grapBindsWithType tx γ
let t2' = splitExistsCases x xs tx t2
splitC (SubC γ' t1 t2')
-- existential at the left hand side is treated like forall
splitC (SubC γ (REx x tx t1) t2)
= do γ' <- (γ, "addExBind 1") += (x, forallExprRefType γ tx)
splitC (SubC γ' t1 t2)
splitC (SubC γ (RAllE x tx t1) (RAllE x2 _ t2)) | x == x2
= do γ' <- (γ, "addExBind 0") += (x, forallExprRefType γ tx)
splitC (SubC γ' t1 t2)
splitC (SubC γ (RAllE x tx t1) t2)
= do γ' <- (γ, "addExBind 2") += (x, forallExprRefType γ tx)
splitC (SubC γ' t1 t2)
splitC (SubC γ t1 (RAllE x tx t2))
= do γ' <- (γ, "addExBind 2") += (x, forallExprRefType γ tx)
splitC (SubC γ' t1 t2)
splitC (SubC γ t1@(RFun x1 r1 r1' _) t2@(RFun x2 r2 r2' _))
= do cs <- bsplitC γ t1 t2
cs' <- splitC (SubC γ r2 r1)
γ' <- (γ, "splitC") += (x2, r2)
let r1x2' = r1' `F.subst1` (x1, F.EVar x2)
cs'' <- splitC (SubC γ' r1x2' r2')
return $ cs ++ cs' ++ cs''
splitC (SubC γ t1@(RAppTy r1 r1' _) t2@(RAppTy r2 r2' _))
= do cs <- bsplitC γ t1 t2
cs' <- splitC (SubC γ r1 r2)
cs'' <- splitC (SubC γ r1' r2')
return $ cs ++ cs' ++ cs''
splitC (SubC γ t1 (RAllP p t))
= splitC $ SubC γ t1 t'
where t' = fmap (replacePredsWithRefs su) t
su = (uPVar p, pVartoRConc p)
splitC (SubC _ t1@(RAllP _ _) t2)
= errorstar $ "Predicate in lhs of constrain:" ++ showpp t1 ++ "\n<:\n" ++ showpp t2
-- = splitC $ SubC γ t' t2
-- where t' = fmap (replacePredsWithRefs su) t
-- su = (uPVar p, pVartoRConc p)
splitC (SubC γ (RAllT α1 t1) (RAllT α2 t2))
| α1 == α2
= splitC $ SubC γ t1 t2
| otherwise
= splitC $ SubC γ t1 t2'
where t2' = subsTyVar_meet' (α2, RVar α1 F.top) t2
splitC (SubC γ t1@(RApp _ _ _ _) t2@(RApp _ _ _ _))
= do (t1',t2') <- unifyVV t1 t2
cs <- bsplitC γ t1' t2'
γ' <- γ `extendEnvWithVV` t1'
let RApp c t1s r1s _ = t1'
let RApp c' t2s r2s _ = t2'
let tyInfo = rTyConInfo c
cscov <- splitCIndexed γ' t1s t2s $ covariantTyArgs tyInfo
cscon <- splitCIndexed γ' t2s t1s $ contravariantTyArgs tyInfo
cscov' <- rsplitCIndexed γ' r1s r2s $ covariantPsArgs tyInfo
cscon' <- rsplitCIndexed γ' r2s r1s $ contravariantPsArgs tyInfo
return $ cs ++ cscov ++ cscon ++ cscov' ++ cscon'
splitC (SubC γ t1@(RVar a1 _) t2@(RVar a2 _))
| a1 == a2
= bsplitC γ t1 t2
splitC (SubC _ (RCls c1 _) (RCls c2 _)) | c1 == c2
= return []
splitC c@(SubC _ t1 t2)
= errorstar $ "(Another Broken Test!!!) splitc unexpected: " ++ showpp t1 ++ "\n\n" ++ showpp t2
splitCIndexed γ t1s t2s indexes
= concatMapM splitC (zipWith (SubC γ) t1s' t2s')
where t1s' = (L.!!) t1s <$> indexes
t2s' = (L.!!) t2s <$> indexes
rsplitCIndexed γ t1s t2s indexes
= concatMapM (rsplitC γ) (safeZip "rsplitC" t1s' t2s')
where t1s' = (L.!!) t1s <$> indexes
t2s' = (L.!!) t2s <$> indexes
bsplitC γ t1 t2 = pruneRefs <$> get >>= return . bsplitC' γ t1 t2
bsplitC' γ t1 t2 pflag
| F.isFunctionSortedReft r1' && F.isNonTrivialSortedReft r2'
= [F.subC γ' F.PTrue (r1' {F.sr_reft = F.top}) r2' Nothing tag ci]
| F.isNonTrivialSortedReft r2'
= [F.subC γ' F.PTrue r1' r2' Nothing tag ci]
| otherwise
= []
where
γ' = fe_binds $ fenv γ
r1' = rTypeSortedReft' pflag γ t1
r2' = rTypeSortedReft' pflag γ t2
ci = Ci src err
tag = getTag γ
err = Just $ ErrSubType src (text "subtype") t1 t2
src = loc γ
unifyVV t1@(RApp c1 _ _ _) t2@(RApp c2 _ _ _)
= do vv <- (F.vv . Just) <$> fresh
return $ (shiftVV t1 vv, (shiftVV t2 vv) ) -- {rt_pargs = r2s'})
rsplitC _ (RMono _ _, RMono _ _)
= errorstar "RefTypes.rsplitC on RMono"
rsplitC γ (t1@(RPoly s1 r1), t2@(RPoly s2 r2))
= do γ' <- foldM (++=) γ [("rsplitC1", x, ofRSort s) | (x, s) <- s2]
splitC (SubC γ' (F.subst su r1) r2)
where su = F.mkSubst [(x, F.EVar y) | (x, y) <- zip (fst <$> s1) (fst <$> s2)]
rsplitC _ _
= errorstar "rsplit Rpoly - RMono"
-----------------------------------------------------------
-------------------- Generation: Types --------------------
-----------------------------------------------------------
data CGInfo = CGInfo { hsCs :: ![SubC]
, hsWfs :: ![WfC]
, fixCs :: ![FixSubC]
, fixWfs :: ![FixWfC]
, globals :: !F.FEnv
, freshIndex :: !Integer
, binds :: !F.BindEnv
, annotMap :: !(AnnInfo Annot)
, tyConInfo :: !(M.HashMap TC.TyCon RTyCon)
, specQuals :: ![F.Qualifier]
, specDecr :: ![(Var, [Int])]
, specLVars :: !(S.HashSet Var)
, specLazy :: !(S.HashSet Var)
, tyConEmbed :: !(F.TCEmb TC.TyCon)
, kuts :: !(F.Kuts)
, lits :: ![(F.Symbol, F.Sort)]
, tcheck :: !Bool
, pruneRefs :: !Bool
, logWarn :: ![String]
} -- deriving (Data, Typeable)
instance PPrint CGInfo where
pprint cgi = {-# SCC "ppr_CGI" #-} ppr_CGInfo cgi
ppr_CGInfo cgi
= (text "*********** Haskell SubConstraints ***********")
$$ (pprint $ hsCs cgi)
$$ (text "*********** Haskell WFConstraints ************")
$$ (pprint $ hsWfs cgi)
$$ (text "*********** Fixpoint SubConstraints **********")
$$ (F.toFix $ fixCs cgi)
$$ (text "*********** Fixpoint WFConstraints ************")
$$ (F.toFix $ fixWfs cgi)
$$ (text "*********** Fixpoint Kut Variables ************")
$$ (F.toFix $ kuts cgi)
$$ (text "*********** Literals in Source ************")
$$ (pprint $ lits cgi)
type CG = State CGInfo
initCGI cfg info = CGInfo {
hsCs = []
, hsWfs = []
, fixCs = []
, fixWfs = []
, globals = globs
, freshIndex = 0
, binds = F.emptyBindEnv
, annotMap = AI M.empty
, tyConInfo = tyi
, specQuals = qualifiers spc
++ specificationQualifiers (maxParams cfg) (info {spec = spec'})
, tyConEmbed = tce
, kuts = F.ksEmpty
, lits = coreBindLits tce info
, specDecr = decr spc
, specLVars = lvars spc
, specLazy = lazy spc
, tcheck = not $ notermination cfg
, pruneRefs = not $ noPrune cfg
, logWarn = []
}
where
tce = tcEmbeds spc
spc = spec info
spec' = spc {tySigs = [ (x, addTyConInfo tce tyi <$> t) | (x, t) <- tySigs spc] }
tyi = makeTyConInfo (tconsP spc)
globs = F.fromListSEnv . map mkSort $ meas spc
mkSort = mapSnd (rTypeSortedReft tce . val)
coreBindLits tce info
= sortNub $ [ (x, so) | (_, Just (F.ELit x so)) <- lconsts]
++ [ (dconToSym dc, dconToSort dc) | dc <- dcons]
where
lconsts = literalConst tce <$> literals (cbs info)
dcons = filter isDCon $ impVars info
dconToSort = typeSort tce . expandTypeSynonyms . varType
dconToSym = dataConSymbol . idDataCon
isDCon x = isDataConWorkId x && not (hasBaseTypeVar x)
extendEnvWithVV γ t
| F.isNontrivialVV vv
= (γ, "extVV") += (vv, t)
| otherwise
= return γ
where vv = rTypeValueVar t
{- see tests/pos/polyfun for why you need everything in fixenv -}
(++=) :: CGEnv -> (String, F.Symbol, SpecType) -> CG CGEnv
γ ++= (_, x, t')
= do idx <- fresh
let t = normalize γ {-x-} idx t'
let γ' = γ { renv = insertREnv x t (renv γ) }
pflag <- pruneRefs <$> get
is <- if isBase t
then liftM single $ addBind x $ rTypeSortedReft' pflag γ' t
else addClassBind t
return $ γ' { fenv = insertsFEnv (fenv γ) is }
rTypeSortedReft' pflag γ
| pflag
= pruneUnsortedReft (fe_env $ fenv γ) . f
| otherwise
= f
where f = rTypeSortedReft (emb γ)
(+++=) :: (CGEnv, String) -> (F.Symbol, CoreExpr, SpecType) -> CG CGEnv
(γ, msg) +++= (x, e, t) = (γ{lcb = M.insert x e (lcb γ)}, "+++=") += (x, t)
(+=) :: (CGEnv, String) -> (F.Symbol, SpecType) -> CG CGEnv
(γ, msg) += (x, r)
| x == F.dummySymbol
= return γ
| x `memberREnv` (renv γ)
= err
| otherwise
= γ ++= (msg, x, r)
where err = errorstar $ msg ++ " Duplicate binding for "
++ F.symbolString x
++ "\n New: " ++ showpp r
++ "\n Old: " ++ showpp (x `lookupREnv` (renv γ))
γ -= x = γ {renv = deleteREnv x (renv γ), lcb = M.delete x (lcb γ)}
(??=) :: CGEnv -> F.Symbol -> CG SpecType
γ ??= x
= case M.lookup x (lcb γ) of
Just e -> consE (γ-=x) e
Nothing -> return $ γ ?= x
(?=) :: CGEnv -> F.Symbol -> SpecType
γ ?= x = fromMaybe err $ lookupREnv x (renv γ)
where err = errorstar $ "EnvLookup: unknown "
++ showpp x
++ " in renv "
++ showpp (renv γ)
normalize' γ x idx t = traceShow ("normalize " ++ showpp x ++ " idx = " ++ show idx ++ " t = " ++ showpp t) $ normalize γ idx t
normalize γ idx
= addRTyConInv (invs γ)
. normalizeVV idx
. normalizePds
normalizeVV idx t@(RApp _ _ _ _)
| not (F.isNontrivialVV (rTypeValueVar t))
= shiftVV t (F.vv $ Just idx)
normalizeVV _ t
= t
shiftVV t@(RApp _ ts _ r) vv'
= t { rt_args = F.subst1 ts (rTypeValueVar t, F.EVar vv') }
{ rt_reft = (`F.shiftVV` vv') <$> r }
shiftVV t _
= t -- errorstar $ "shiftVV: cannot handle " ++ showpp t
addBind :: F.Symbol -> F.SortedReft -> CG ((F.Symbol, F.Sort), F.BindId)
addBind x r
= do st <- get
let (i, bs') = F.insertBindEnv x r (binds st)
put $ st { binds = bs' }
return ((x, F.sr_sort r), i) -- traceShow ("addBind: " ++ showpp x) i
addClassBind :: SpecType -> CG [((F.Symbol, F.Sort), F.BindId)]
addClassBind = mapM (uncurry addBind) . classBinds
-- addClassBind (RCls c ts)
-- | isNumericClass c
-- = do let numReft = F.trueSortedReft F.FNum
-- let numVars = [rTyVarSymbol a | (RVar a _) <- ts]
-- is <- forM numVars (`addBind` numReft)
-- return is
-- addClassBind _
-- = return []
addC :: SubC -> String -> CG ()
addC !c@(SubC _ t1 t2) _msg
= -- trace ("addC " ++ _msg++ showpp t1 ++ "\n <: \n" ++ showpp t2 ) $
modify $ \s -> s { hsCs = c : (hsCs s) }
addW :: WfC -> CG ()
addW !w = modify $ \s -> s { hsWfs = w : (hsWfs s) }
addWarning :: String -> CG ()
addWarning w = modify $ \s -> s { logWarn = w : (logWarn s) }
-- | Used to generate "cut" kvars for fixpoint. Typically, KVars for recursive definitions.
addKuts :: SpecType -> CG ()
addKuts !t = modify $ \s -> s { kuts = updKuts (kuts s) t }
where
updKuts :: F.Kuts -> SpecType -> F.Kuts
updKuts = foldReft (F.ksUnion . (F.reftKVars . ur_reft) )
-- | Used for annotation binders (i.e. at binder sites)
addIdA :: Var -> Annot -> CG ()
addIdA !x !t = modify $ \s -> s { annotMap = upd $ annotMap s }
where
loc = getSrcSpan x
upd m@(AI z) = if boundRecVar loc m then m else addA loc (Just x) t m
-- loc = traceShow ("addIdA: " ++ show x ++ " :: " ++ showpp t ++ " at ") $ getSrcSpan x
boundRecVar l (AI m) = not $ null [t | (_, RDf t) <- M.lookupDefault [] l m]
-- | Used for annotating reads (i.e. at Var x sites)
addLocA :: Maybe Var -> SrcSpan -> Annot -> CG ()
addLocA !xo !l !t
= modify $ \s -> s { annotMap = addA l xo t $ annotMap s }
-- | Used to update annotations for a location, due to (ghost) predicate applications
updateLocA (_:_) (Just l) t = addLocA Nothing l (Use t)
updateLocA _ _ _ = return ()
addA !l !xo@(Just _) !t !(AI m)
| isGoodSrcSpan l
= AI $ inserts l (xo, t) m
addA !l !xo@(Nothing) !t !(AI m)
| l `M.member` m -- only spans known to be variables
= AI $ inserts l (xo, t) m
addA _ _ _ !a
= a
-------------------------------------------------------------------
------------------------ Generation: Freshness --------------------
-------------------------------------------------------------------
-- | Right now, we generate NO new pvars. Rather than clutter code
-- with `uRType` calls, put it in one place where the above invariant
-- is /obviously/ enforced.
freshTy :: CoreExpr -> Type -> CG SpecType
freshTy _ = liftM uRType . refresh . ofType
-- To revert to the old setup, just do
-- freshTy_pretty = freshTy
-- freshTy_pretty e τ = refresh $ {-traceShow ("exprRefType: " ++ F.showFix e) $-} exprRefType e
freshTy_pretty e _ = do t <- refresh $ {-traceShow ("exprRefType: " ++ F.showFix e) $-} exprRefType e
return $ uRType t
-- TODO: remove freshRSort?
-- freshRSort :: CoreExpr -> RSort -> CG SpecType
-- freshRSort e = freshTy e . toType
trueTy :: Type -> CG SpecType
trueTy t
= do t <- true $ ofType t
tyi <- liftM tyConInfo get
tce <- tyConEmbed <$> get
return $ addTyConInfo tce tyi (uRType t)
refreshArgs t
= do xs' <- mapM (\_ -> fresh) xs
let su = F.mkSubst $ zip xs (F.EVar <$> xs')
return $ mkArrow αs πs (zip xs' (F.subst su <$> ts)) (F.subst su tbd)
where (αs, πs, t0) = bkUniv t
(xs, ts, tbd) = bkArrow t0
instance Freshable CG Integer where
fresh = do s <- get
let n = freshIndex s
put $ s { freshIndex = n + 1 }
return n
instance TCInfo CG where
getTyConInfo = tyConInfo <$> get
getTyConEmbed = tyConEmbed <$> get
addTyConInfo tce tyi = mapBot (expandRApp tce tyi)
-------------------------------------------------------------------------------
----------------------- TERMINATION TYPE ---------------------------------------
-------------------------------------------------------------------------------
makeDecrIndex :: (Var, SpecType)-> CG [Int]
makeDecrIndex (x, t)
= do hint <- checkHint' . L.lookup x . specDecr <$> get
case dindex of
Nothing -> addWarning msg >> return []
Just i -> return $ fromMaybe [i] hint
where ts = snd3 $ bkArrow $ thd3 $ bkUniv t
checkHint' = checkHint x ts isDecreasing
dindex = L.findIndex isDecreasing ts
msg = printf "%s: No decreasing parameter" $ showPpr (getSrcSpan x)
recType ((_, []), (_, [], t))
= t
recType ((vs, indexc), (x, index, t))
= makeRecType t v dxt index
where v = (vs !!) <$> indexc
dxt = (xts !!) <$> index
loc = showPpr (getSrcSpan x)
xts' = bkArrow $ thd3 $ bkUniv t
xts = zip (fst3 xts') (snd3 xts')
msg' = printf "%s: No decreasing argument on %s with %s"
msg = printf "%s: No decreasing parameter" loc
loc (showPpr x) (showPpr vs)
checkIndex (x, vs, t, index)
= do mapM_ (safeLogIndex msg' vs) index
mapM (safeLogIndex msg ts) index
where loc = showPpr (getSrcSpan x)
ts = snd3 $ bkArrow $ thd3 $ bkUniv t
msg' = printf "%s: No decreasing argument on %s with %s"
msg = printf "%s: No decreasing parameter" loc
loc (showPpr x) (showPpr vs)
-- MOVE THE SAME LENS CHECKS BEFORE - TO DO IT ONCE FOR ALL FUNCTIOS
-- makeRecType t vs dxs is | not sameLens
-- = errorstar "Constraint.makeRecType: invalid arguments"
-- where sameLens = (length vs) == (length is) && (length dxs) == (length is)
--
makeRecType t vs' dxs' is
= mkArrow αs πs xts' tbd
where xts' = replaceN (last is) (makeDecrType vdxs) xts
vdxs = zip vs dxs
xts = zip xs ts
vs = vs'
dxs = dxs'
(αs, πs, t0) = bkUniv t
(xs, ts, tbd) = bkArrow t0
safeLogIndex err ls n
| n >= length ls
= addWarning err >> return Nothing
| otherwise
= return $ Just $ ls !! n
checkHint _ _ _ Nothing
= Nothing
checkHint x ts f (Just ns) | L.sort ns /= ns
= errorstar $ printf "%s: The hints should be increasing" loc
where loc = showPpr $ getSrcSpan x
checkHint x ts f (Just ns)
= Just $ catMaybes (checkValidHint x ts f <$> ns)
checkValidHint x ts f n
| n < 0 || n >= length ts = errorstar err
| f (ts L.!! n) = Just n
| otherwise = errorstar err
where err = printf "%s: Invalid Hint %d for %s" loc (n+1) (showPpr x)
loc = showPpr $ getSrcSpan x
-------------------------------------------------------------------
-------------------- Generation: Corebind -------------------------
-------------------------------------------------------------------
consCBLet γ cb
= do tflag <- tcheck <$> get
consCB tflag γ cb
consCBTop γ cb
= do oldtcheck <- tcheck <$> get
strict <- specLazy <$> get
let tflag = oldtcheck && (tcond cb strict)
modify $ \s -> s{tcheck = tflag}
γ' <- consCB tflag γ cb
modify $ \s -> s{tcheck = oldtcheck}
return γ'
tcond cb strict
= not $ any (\x -> S.member x strict || isInternal x) (binds cb)
where binds (NonRec x _) = [x]
binds (Rec xes) = fst $ unzip xes
-------------------------------------------------------------------
consCB :: Bool -> CGEnv -> CoreBind -> CG CGEnv
-------------------------------------------------------------------
consCB tflag γ (Rec xes) | tflag
= do xets <- forM xes $ \(x, e) -> liftM (x, e,) (varTemplate γ (x, Just e))
ts <- mapM refreshArgs $ (fromJust . thd3 <$> xets)
let vs = zipWith collectArgs ts es
is <- checkSameLens <$> mapM makeDecrIndex (zip xs ts)
let xeets = (\vis -> [(vis, x) | x <- zip3 xs is ts]) <$> (zip vs is)
checkEqTypes . L.transpose <$> mapM checkIndex (zip4 xs vs ts is)
let rts = (recType <$>) <$> xeets
let xts = zip xs (Just <$> ts)
γ' <- foldM extender γ xts
let γs = [γ' `withTRec` (zip xs rts') | rts' <- rts]
let xets' = zip3 xs es (Just <$> ts)
mapM_ (uncurry $ consBind True) (zip γs xets')
return γ'
where dmapM f = sequence . (mapM f <$>)
(xs, es) = unzip xes
collectArgs = collectArguments . length . fst3 . bkArrow . thd3 . bkUniv
checkEqTypes = map (checkAll err1 toRSort . catMaybes)
checkSameLens = checkAll err2 length
err1 = printf "%s: The decreasing parameters should be of same type" loc
err2 = printf "%s: All Recursive functions should have the same number of decreasing parameters" loc
loc = showPpr $ getSrcSpan (head xs)
checkAll _ _ [] = []
checkAll err f (x:xs) | all (==(f x)) (f <$> xs) = (x:xs)
| otherwise = errorstar err
-- TODO : no termination check:
-- check that the result type is trivial!
consCB _ γ (Rec xes)
= do xets <- forM xes $ \(x, e) -> liftM (x, e,) (varTemplate γ (x, Just e))
let xts = [(x, to) | (x, _, to) <- xets, not (isGrty x)]
γ' <- foldM extender (γ `withRecs` (fst <$> xts)) xts
mapM_ (consBind True γ') xets
return γ'
where isGrty x = (varSymbol x) `memberREnv` (grtys γ)
consCB _ γ (NonRec x e)
= do to <- varTemplate γ (x, Nothing)
to' <- consBind False γ (x, e, to)
extender γ (x, to')
consBind isRec γ (x, e, Just spect)
= do let γ' = (γ `setLoc` getSrcSpan x) `setBind` x
γπ <- foldM addPToEnv γ' πs
cconsE γπ e spect
addIdA x (defAnn isRec spect)
return Nothing
where πs = snd3 $ bkUniv spect
consBind isRec γ (x, e, Nothing)
= do t <- unifyVar γ x <$> consE (γ `setBind` x) e
addIdA x (defAnn isRec t)
return $ Just t
defAnn True = RDf
defAnn False = Def
addPToEnv γ π
= do γπ <- γ ++= ("addSpec1", pname π, toPredType π)
foldM (++=) γπ [("addSpec2", x, ofRSort t) | (t, x, _) <- pargs π]
extender γ (x, Just t) = γ ++= ("extender", varSymbol x, t)
extender γ _ = return γ
addBinders γ0 x' cbs = foldM (++=) (γ0 -= x') [("addBinders", x, t) | (x, t) <- cbs]
varTemplate :: CGEnv -> (Var, Maybe CoreExpr) -> CG (Maybe SpecType)
varTemplate γ (x, eo)
= case (eo, lookupREnv (varSymbol x) (grtys γ)) of
(_, Just t) -> return $ Just t
(Just e, _) -> do t <- unifyVar γ x <$> freshTy_pretty e (exprType e)
addW (WfC γ t)
addKuts t
return $ Just t
(_, _) -> return Nothing
unifyVar γ x rt = unify (getPrType γ (varSymbol x)) rt
-------------------------------------------------------------------
-------------------- Generation: Expression -----------------------
-------------------------------------------------------------------
----------------------- Type Checking -----------------------------
cconsE :: CGEnv -> Expr Var -> SpecType -> CG ()
-------------------------------------------------------------------
cconsLazyLet γ (Let (NonRec x ex) e) t
= do tx <- {-(`strengthen` xr) <$>-} trueTy (varType x)
γ' <- (γ, "Let NonRec") +++= (x', ex, tx)
cconsE γ' e t
where xr = uTop $ F.symbolReft x'
x' = varSymbol x
cconsE γ e@(Let b@(NonRec x _) ee) t
= do sp <- specLVars <$> get
if (x `S.member` sp) || isDefLazyVar x'
then cconsLazyLet γ e t
else do γ' <- consCBLet γ b
cconsE γ' ee t
where isDefLazyVar y = "fail" `L.isPrefixOf` y
x' = showPpr x
cconsE γ (Let b e) t
= do γ' <- consCBLet γ b
cconsE γ' e t
cconsE γ (Case e x _ cases) t
= do γ' <- consCB False γ $ NonRec x e
forM_ cases $ cconsCase γ' x t nonDefAlts
where nonDefAlts = [a | (a, _, _) <- cases, a /= DEFAULT]
cconsE γ (Lam α e) (RAllT α' t) | isTyVar α
= cconsE γ e $ subsTyVar_meet' (α', rVar α) t
cconsE γ (Lam x e) (RFun y ty t _)
| not (isTyVar x)
= do γ' <- (γ, "cconsE") += (varSymbol x, ty)
cconsE γ' e (t `F.subst1` (y, F.EVar $ varSymbol x))
addIdA x (Def ty)
cconsE γ (Tick tt e) t
= cconsE (γ `setLoc` tickSrcSpan tt) e t
cconsE γ e@(Cast _ _) t
= do t' <- trueTy $ exprType e
addC (SubC γ t' t) ("cconsE Cast" ++ showPpr e)
cconsE γ e (RAllP p t)
= cconsE γ e t'
where t' = fmap (replacePredsWithRefs su) t
su = (uPVar p, pVartoRConc p)
cconsE γ e t
= do te <- consE γ e
te' <- instantiatePreds γ e te
addC (SubC γ te' t) ("cconsE" ++ showPpr e)
instantiatePreds γ e (RAllP p t)
= do s <- freshPredRef γ e p
return $ replacePreds "consE" t [(p, s)]
instantiatePreds _ _ t
= return t
----------------------- Type Synthesis ----------------------------
consE :: CGEnv -> Expr Var -> CG SpecType
-------------------------------------------------------------------
consE γ (Var x)
= do t <- varRefType γ x
addLocA (Just x) (loc γ) (varAnn γ x t)
return t
consE γ (Lit c)
= return $ uRType $ literalFRefType (emb γ) c
consE γ (App e (Type τ))
= do RAllT α te <- liftM (checkAll ("Non-all TyApp with expr", e)) $ consE γ e
t <- if isGeneric α te then freshTy e τ {- =>> addKuts -} else trueTy τ
addW $ WfC γ t
return $ subsTyVar_meet' (α, t) te
consE γ e'@(App e a) | eqType (exprType a) predType
= do t0 <- consE γ e
case t0 of
RAllP p t -> do s <- freshPredRef γ e' p
return $ replacePreds "consE" t [(p, s)] {- =>> addKuts -}
_ -> return t0
consE γ e'@(App e a)
= do ([], πs, te) <- bkUniv <$> consE γ e
zs <- mapM (\π -> liftM ((π,)) $ freshPredRef γ e' π) πs
te' <- return (replacePreds "consE" te zs) {- =>> addKuts -}
(γ', te'') <- dropExists γ te'
updateLocA πs (exprLoc e) te''
let (RFun x tx t _) = checkFun ("Non-fun App with caller", e') te''
cconsE γ' a tx
return $ maybe (checkUnbound γ' e' x t) (F.subst1 t . (x,)) (argExpr γ a)
-- where err = errorstar $ "consE: App crashes on" ++ showPpr a
consE γ (Lam α e) | isTyVar α
= liftM (RAllT (rTyVar α)) (consE γ e)
consE γ e@(Lam x e1)
= do tx <- freshTy (Var x) τx
γ' <- ((γ, "consE") += (varSymbol x, tx))
t1 <- consE γ' e1
addIdA x (Def tx)
addW $ WfC γ tx
return $ rFun (varSymbol x) tx t1
where FunTy τx _ = exprType e
consE γ e@(Let _ _)
= cconsFreshE γ e
consE γ e@(Case _ _ _ _)
= cconsFreshE γ e
consE γ (Tick tt e)
= do t <- consE (γ `setLoc` l) e
addLocA Nothing l (Use t)
return t
where l = {- traceShow ("tickSrcSpan: e = " ++ showPpr e) $ -} tickSrcSpan tt
consE γ e@(Cast _ _)
= trueTy $ exprType e
consE γ e@(Coercion _)
= trueTy $ exprType e
consE _ e
= errorstar $ "consE cannot handle " ++ showPpr e
cconsFreshE γ e
= do t <- freshTy e $ exprType e
addW $ WfC γ t
cconsE γ e t
return t
checkUnbound γ e x t
| x `notElem` (F.syms t) = t
| otherwise = errorstar $ "consE: cannot handle App " ++ showPpr e ++ " at " ++ showPpr (loc γ)
dropExists γ (REx x tx t) = liftM (, t) $ (γ, "dropExists") += (x, tx)
dropExists γ t = return (γ, t)
-------------------------------------------------------------------------------------
cconsCase :: CGEnv -> Var -> SpecType -> [AltCon] -> (AltCon, [Var], CoreExpr) -> CG ()
-------------------------------------------------------------------------------------
cconsCase γ x t _ (DataAlt c, ys, ce)
= do xt0 <- checkTyCon ("checkTycon cconsCase", x) <$> γ ??= x'
tdc <- γ ??= (dataConSymbol c)
let (rtd, yts, _) = unfoldR c tdc (shiftVV xt0 x') ys
let r1 = dataConReft c ys'
let r2 = dataConMsReft rtd ys'
let xt = xt0 `strengthen` (uTop (r1 `F.meet` r2))
let cbs = safeZip "cconsCase" (x':ys') (xt0:yts)
cγ' <- addBinders γ x' cbs
cγ <- addBinders cγ' x' [(x', xt)]
cconsE cγ ce t
where (x':ys') = varSymbol <$> (x:ys)
cconsCase γ x t acs (a, _, ce)
= do let x' = varSymbol x
xt' <- (`strengthen` uTop (altReft γ acs a)) <$> (γ ??= x')
cγ <- addBinders γ x' [(x', xt')]
cconsE cγ ce t
altReft γ _ (LitAlt l) = literalFReft (emb γ) l
altReft γ acs DEFAULT = mconcat [notLiteralReft l | LitAlt l <- acs]
where notLiteralReft = maybe F.top F.notExprReft . snd . literalConst (emb γ)
altReft _ _ _ = error "Constraint : altReft"
unfoldR dc td (RApp _ ts rs _) ys = (t3, tvys ++ yts, rt)
where
tbody = instantiatePvs (instantiateTys td ts) $ reverse rs
(ys0, yts', rt) = safeBkArrow $ instantiateTys tbody tvs'
(t3:yts) = F.subst su <$> (rt:yts')
su = F.mkSubst [(x, F.EVar y) | (x, y)<- zip ys0 ys']
(αs, ys') = mapSnd (varSymbol <$>) $ L.partition isTyVar ys
tvs' = rVar <$> αs
tvys = ofType . varType <$> αs
unfoldR _ _ _ _ = error "Constraint.hs : unfoldR"
instantiateTys = foldl' go
where go (RAllT α tbody) t = subsTyVar_meet' (α, t) tbody
go _ _ = errorstar "Constraint.instanctiateTy"
instantiatePvs = foldl' go
where go (RAllP p tbody) r = replacePreds "instantiatePv" tbody [(p, r)]
go _ _ = errorstar "Constraint.instanctiatePv"
instance Show CoreExpr where
show = showPpr
checkTyCon _ t@(RApp _ _ _ _) = t
checkTyCon x t = checkErr x t --errorstar $ showPpr x ++ "type: " ++ showPpr t
-- checkRPred _ t@(RAll _ _) = t
-- checkRPred x t = checkErr x t
checkFun _ t@(RFun _ _ _ _) = t
checkFun x t = checkErr x t
checkAll _ t@(RAllT _ _) = t
checkAll x t = checkErr x t
checkErr (msg, e) t = errorstar $ msg ++ showPpr e ++ "type: " ++ showpp t
varAnn γ x t
| x `S.member` recs γ
= Loc (getSrcSpan' x)
| otherwise
= Use t
getSrcSpan' x
| loc == noSrcSpan
= traceShow ("myGetSrcSpan: No Location for: " ++ showPpr x) $ loc
| otherwise
= loc
where loc = getSrcSpan x
-----------------------------------------------------------------------
---------- Helpers: Creating Fresh Refinement ------------------ ------
-----------------------------------------------------------------------
truePredRef :: (PPrint r, F.Reftable r) => PVar (RRType r) -> CG SpecType
truePredRef (PV _ τ _)
= trueTy (toType τ)
freshPredRef :: CGEnv -> CoreExpr -> PVar RSort -> CG (Ref RSort RReft SpecType)
freshPredRef γ e (PV n τ as)
= do t <- freshTy e (toType τ)
args <- mapM (\_ -> fresh) as
let targs = zip args (fst3 <$> as)
γ' <- foldM (++=) γ [("freshPredRef", x, ofRSort τ) | (x, τ) <- targs]
addW $ WfC γ' t
return $ RPoly targs t
-----------------------------------------------------------------------
---------- Helpers: Creating Refinement Types For Various Things ------
-----------------------------------------------------------------------
argExpr :: CGEnv -> CoreExpr -> Maybe F.Expr
argExpr _ (Var vy) = Just $ F.EVar $ varSymbol vy
argExpr γ (Lit c) = snd $ literalConst (emb γ) c
argExpr γ (Tick _ e) = argExpr γ e
argExpr _ e = errorstar $ "argExpr: " ++ showPpr e
varRefType γ x = liftM (varRefType' γ x) (γ ??= varSymbol x)
varRefType' γ x t'
| Just tys <- trec γ
= maybe t (`strengthen` xr) (x' `M.lookup` tys)
| otherwise
= t
where t = t' `strengthen` xr
xr = uTop $ F.symbolReft $ varSymbol x
x' = varSymbol x
-- TODO: should only expose/use subt. Not subsTyVar_meet
subsTyVar_meet' (α, t) = subsTyVar_meet (α, toRSort t, t)
-----------------------------------------------------------------------
--------------- Forcing Strictness ------------------------------------
-----------------------------------------------------------------------
instance NFData CGEnv where
rnf (CGE x1 x2 x3 x4 x5 x6 x7 x8 _ x9 x10 _ _)
= x1 `seq` rnf x2 `seq` seq x3 `seq` x4 `seq` rnf x5 `seq`
rnf x6 `seq` x7 `seq` rnf x8 `seq` rnf x9 `seq` rnf x10
instance NFData FEnv where
rnf (FE x1 _) = rnf x1
instance NFData SubC where
rnf (SubC x1 x2 x3)
= rnf x1 `seq` rnf x2 `seq` rnf x3
instance NFData Class where
rnf _ = ()
instance NFData RTyCon where
rnf _ = ()
instance NFData Type where
rnf _ = ()
instance NFData WfC where
rnf (WfC x1 x2)
= rnf x1 `seq` rnf x2
instance NFData CGInfo where
rnf x = ({-# SCC "CGIrnf1" #-} rnf (hsCs x)) `seq`
({-# SCC "CGIrnf2" #-} rnf (hsWfs x)) `seq`
({-# SCC "CGIrnf3" #-} rnf (fixCs x)) `seq`
({-# SCC "CGIrnf4" #-} rnf (fixWfs x)) `seq`
({-# SCC "CGIrnf5" #-} rnf (globals x)) `seq`
({-# SCC "CGIrnf6" #-} rnf (freshIndex x)) `seq`
({-# SCC "CGIrnf7" #-} rnf (binds x)) `seq`
({-# SCC "CGIrnf8" #-} rnf (annotMap x)) `seq`
({-# SCC "CGIrnf9" #-} rnf (specQuals x)) `seq`
({-# SCC "CGIrnf10" #-} rnf (kuts x)) `seq`
({-# SCC "CGIrnf10" #-} rnf (lits x))
-------------------------------------------------------------------------------
--------------------- Reftypes from F.Fixpoint Expressions ----------------------
-------------------------------------------------------------------------------
forallExprRefType :: CGEnv -> SpecType -> SpecType
forallExprRefType γ t = t `strengthen` (uTop r')
where r' = maybe F.top (forallExprReft γ) ((F.isSingletonReft) r)
r = F.sr_reft $ rTypeSortedReft (emb γ) t
forallExprReft γ (F.EApp f es) = F.subst su $ F.sr_reft $ rTypeSortedReft (emb γ) t
where (xs,_ , t) = bkArrow $ thd3 $ bkUniv $ forallExprReftLookup γ f
su = F.mkSubst $ safeZip "fExprRefType" xs es
forallExprReft γ (F.EVar x) = F.sr_reft $ rTypeSortedReft (emb γ) t
where (_,_ , t) = bkArrow $ thd3 $ bkUniv $ forallExprReftLookup γ x
forallExprReft _ e = F.exprReft e
forallExprReftLookup γ x = γ ?= x'
where x' = fromMaybe err (varSymbol <$> F.lookupSEnv x γ')
γ' = syenv γ
err = errorstar $ "exReftLookup: unknown " ++ showpp x ++ " in " ++ F.showFix γ'
-- withReft (RApp c ts rs _) r' = RApp c ts rs r'
-- withReft (RVar a _) r' = RVar a r'
-- withReft t _ = t
grapBindsWithType tx γ
= fst <$> toListREnv (filterREnv ((== toRSort tx) . toRSort) (renv γ))
splitExistsCases z xs tx
= fmap $ fmap (exrefAddEq z xs tx)
exrefAddEq z xs t (F.Reft(s, rs))
= F.Reft(s, [F.RConc (F.POr [ pand x | x <- xs])])
where tref = fromMaybe F.top $ stripRTypeBase t
pand x = F.PAnd $ (substzx x) (fFromRConc <$> rs)
++ exrefToPred x tref
substzx x = F.subst (F.mkSubst [(z, F.EVar x)])
exrefToPred x uref
= F.subst (F.mkSubst [(v, F.EVar x)]) ((fFromRConc <$> r))
where (F.Reft(v, r)) = ur_reft uref
fFromRConc (F.RConc p) = p
fFromRConc _ = errorstar "can not hanlde existential type with kvars"
-------------------------------------------------------------------------------
-------------------- Cleaner Signatures For Rec-bindings ----------------------
-------------------------------------------------------------------------------
exprLoc :: CoreExpr -> Maybe SrcSpan
exprLoc (Tick tt _) = Just $ tickSrcSpan tt
exprLoc (App e a) | isType a = exprLoc e
exprLoc _ = Nothing
isType (Type _) = True
isType a = eqType (exprType a) predType
exprRefType :: CoreExpr -> RefType
exprRefType = exprRefType_ M.empty
exprRefType_ :: M.HashMap Var RefType -> CoreExpr -> RefType
exprRefType_ γ (Let b e)
= exprRefType_ (bindRefType_ γ b) e
exprRefType_ γ (Lam α e) | isTyVar α
= RAllT (rTyVar α) (exprRefType_ γ e)
exprRefType_ γ (Lam x e)
= rFun (varSymbol x) (ofType $ varType x) (exprRefType_ γ e)
exprRefType_ γ (Tick _ e)
= exprRefType_ γ e
exprRefType_ γ (Var x)
= M.lookupDefault (ofType $ varType x) x γ
exprRefType_ _ e
= ofType $ exprType e
bindRefType_ γ (Rec xes)
= extendγ γ [(x, exprRefType_ γ e) | (x,e) <- xes]
bindRefType_ γ (NonRec x e)
= extendγ γ [(x, exprRefType_ γ e)]
extendγ γ xts
= foldr (\(x,t) m -> M.insert x t m) γ xts
-------------------------------------------------------------------
--------- | Strengthening Binders with TyCon Invariants -----------
-------------------------------------------------------------------
type RTyConInv = M.HashMap RTyCon [SpecType]
-- mkRTyConInv :: [Located SpecType] -> RTyConInv
mkRTyConInv ts = group [ (c, t) | t@(RApp c _ _ _) <- strip <$> ts]
where
strip = thd3 . bkUniv . val
addRTyConInv :: RTyConInv -> SpecType -> SpecType
addRTyConInv m t@(RApp c _ _ _)
= case M.lookup c m of
Nothing -> t
Just ts -> foldl' conjoinInvariant' t ts
addRTyConInv _ t
= t
conjoinInvariant' t1 t2
= conjoinInvariantShift t1 t2
conjoinInvariantShift t1 t2
= conjoinInvariant t1 (shiftVV t2 (rTypeValueVar t1))
conjoinInvariant (RApp c ts rs r) (RApp ic its _ ir)
| (c == ic && length ts == length its)
= RApp c (zipWith conjoinInvariantShift ts its) rs (r `F.meet` ir)
conjoinInvariant t@(RApp _ _ _ r) (RVar _ ir)
= t { rt_reft = r `F.meet` ir }
conjoinInvariant t@(RVar _ r) (RVar _ ir)
= t { rt_reft = r `F.meet` ir }
conjoinInvariant t _
= t
---------------------------------------------------------------
----- Refinement Type Environments ----------------------------
---------------------------------------------------------------
newtype REnv = REnv (M.HashMap F.Symbol SpecType) -- deriving (Data, Typeable)
instance PPrint REnv where
pprint (REnv m) = vcat $ map pprxt $ M.toList m
where
pprxt (x, t) = pprint x <> dcolon <> pprint t
instance NFData REnv where
rnf (REnv _) = () -- rnf m
toListREnv (REnv env) = M.toList env
filterREnv f (REnv env) = REnv $ M.filter f env
fromListREnv = REnv . M.fromList
deleteREnv x (REnv env) = REnv (M.delete x env)
insertREnv x y (REnv env) = REnv (M.insert x y env)
lookupREnv x (REnv env) = M.lookup x env
memberREnv x (REnv env) = M.member x env
-- domREnv (REnv env) = M.keys env
-- emptyREnv = REnv M.empty
cgInfoFInfoBot cgi = cgInfoFInfo cgi { specQuals = [] }
cgInfoFInfoKvars cgi kvars = cgInfoFInfo cgi{fixCs = fixCs' ++ trueCs}
where fixCs' = concatMap (updateCs kvars) (fixCs cgi)
trueCs = (`F.trueSubCKvar` (Ci noSrcSpan Nothing)) <$> kvars
cgInfoFInfo cgi
= F.FI { F.cm = M.fromList $ F.addIds $ fixCs cgi
, F.ws = fixWfs cgi
, F.bs = binds cgi
, F.gs = globals cgi
, F.lits = lits cgi
, F.kuts = kuts cgi
, F.quals = specQuals cgi
}
updateCs kvars cs
| null lhskvars || F.isFalse rhs
= [cs]
| all (`elem` kvars) lhskvars && null lhsconcs
= []
| any (`elem` kvars) lhskvars
= [F.removeLhsKvars cs kvars]
| otherwise
= [cs]
where lhskvars = F.reftKVars lhs
rhskvars = F.reftKVars rhs
lhs = F.lhsCs cs
rhs = F.rhsCs cs
F.Reft(_, lhspds) = lhs
lhsconcs = [p | F.RConc p <- lhspds]