X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FbasicTypes%2FBasicTypes.lhs;h=bce1fa069c39782a93091b4519686862aacfb15f;hb=76fcd85d57595f9d864dea60f4d738ff59959326;hp=b10fec9390583fe6dd0912baea3d0f41b7ba4928;hpb=9dd6e1c216993624a2cd74b62ca0f0569c02c26b;p=ghc-hetmet.git diff --git a/ghc/compiler/basicTypes/BasicTypes.lhs b/ghc/compiler/basicTypes/BasicTypes.lhs index b10fec9..bce1fa0 100644 --- a/ghc/compiler/basicTypes/BasicTypes.lhs +++ b/ghc/compiler/basicTypes/BasicTypes.lhs @@ -1,5 +1,5 @@ % -% (c) The GRASP/AQUA Project, Glasgow University, 1997 +% (c) The GRASP/AQUA Project, Glasgow University, 1997-1998 % \section[BasicTypes]{Miscellanous types} @@ -14,33 +14,48 @@ types that \begin{code} module BasicTypes( - Version, Arity, - Unused, unused, - Module, moduleString, pprModule, + Version, bumpVersion, initialVersion, + + Arity, + + DeprecTxt, + Fixity(..), FixityDirection(..), - NewOrData(..), IfaceFlavour(..), TopLevelFlag(..), RecFlag(..) - ) where + defaultFixity, maxPrecedence, + negateFixity, + compareFixity, -#include "HsVersions.h" + IPName(..), ipNameName, mapIPName, -import Outputable -\end{code} + RecFlag(..), isRec, isNonRec, boolToRecFlag, -%************************************************************************ -%* * -\subsection[Unused]{Unused} -%* * -%************************************************************************ + TopLevelFlag(..), isTopLevel, isNotTopLevel, -Used as a placeholder in types. + Boxity(..), isBoxed, -\begin{code} -type Unused = Void + TupCon(..), tupleParens, -unused :: Unused -unused = error "Unused is used!" -\end{code} + OccInfo(..), seqOccInfo, isFragileOcc, isOneOcc, + isDeadOcc, isLoopBreaker, + + InsideLam, insideLam, notInsideLam, + OneBranch, oneBranch, notOneBranch, + + EP(..), + + StrictnessMark(..), isMarkedUnboxed, isMarkedStrict, + + CompilerPhase, + Activation(..), isActive, isNeverActive, isAlwaysActive, + + SuccessFlag(..), succeeded, failed, successIf + ) where +#include "HsVersions.h" + +import FastString( FastString ) +import Outputable +\end{code} %************************************************************************ %* * @@ -61,55 +76,53 @@ type Arity = Int \begin{code} type Version = Int -\end{code} +bumpVersion :: Version -> Version +bumpVersion v = v+1 + +initialVersion :: Version +initialVersion = 1 +\end{code} %************************************************************************ %* * -\subsection[Module]{The name of a module} + Deprecations %* * %************************************************************************ -\begin{code} -type Module = FAST_STRING - -moduleString :: Module -> String -moduleString mod = _UNPK_ mod -pprModule :: Module -> SDoc -pprModule m = ptext m +\begin{code} +type DeprecTxt = FastString -- reason/explanation for deprecation \end{code} %************************************************************************ %* * -\subsection[IfaceFlavour]{IfaceFlavour} +\subsection{Implicit parameter identity} %* * %************************************************************************ -The IfaceFlavour type is used mainly in an imported Name's Provenance -to say whether the name comes from a regular .hi file, or whether it comes -from a hand-written .hi-boot file. This is important, because it has to be -propagated. Suppose +The @IPName@ type is here because it is used in TypeRep (i.e. very +early in the hierarchy), but also in HsSyn. - C.hs imports B - B.hs imports A - A.hs imports C {-# SOURCE -#} ( f ) +\begin{code} +data IPName name + = Dupable name -- ?x: you can freely duplicate this implicit parameter + | Linear name -- %x: you must use the splitting function to duplicate it + deriving( Eq, Ord ) -- Ord is used in the IP name cache finite map + -- (used in HscTypes.OrigIParamCache) -Then in A.hi we may mention C.f, in an inlining. When compiling B we *must not* -read C.f's details from C.hi, even if the latter happens to exist from an earlier -compilation run. So we use the name "C!f" in A.hi, and when looking for an interface -file with details of C!f we look in C.hi-boot. The "!" stuff is recorded in the -IfaceFlavour in the Name of C.f in A. -Not particularly beautiful, but it works. +ipNameName :: IPName name -> name +ipNameName (Dupable n) = n +ipNameName (Linear n) = n -\begin{code} -data IfaceFlavour = HiFile -- The interface was read from a standard interface file - | HiBootFile -- ... or from a handwritten "hi-boot" interface file +mapIPName :: (a->b) -> IPName a -> IPName b +mapIPName f (Dupable n) = Dupable (f n) +mapIPName f (Linear n) = Linear (f n) -instance Text IfaceFlavour where -- Just used in debug prints of lex tokens - showsPrec n HiFile s = s - showsPrec n HiBootFile s = "!" ++ s +instance Outputable name => Outputable (IPName name) where + ppr (Dupable n) = char '?' <> ppr n -- Ordinary implicit parameters + ppr (Linear n) = char '%' <> ppr n -- Splittable implicit parameters \end{code} @@ -120,38 +133,61 @@ instance Text IfaceFlavour where -- Just used in debug prints of lex tokens %************************************************************************ \begin{code} +------------------------ data Fixity = Fixity Int FixityDirection -data FixityDirection = InfixL | InfixR | InfixN - deriving(Eq) instance Outputable Fixity where ppr (Fixity prec dir) = hcat [ppr dir, space, int prec] +instance Eq Fixity where -- Used to determine if two fixities conflict + (Fixity p1 dir1) == (Fixity p2 dir2) = p1==p2 && dir1 == dir2 + +------------------------ +data FixityDirection = InfixL | InfixR | InfixN + deriving(Eq) + instance Outputable FixityDirection where ppr InfixL = ptext SLIT("infixl") ppr InfixR = ptext SLIT("infixr") ppr InfixN = ptext SLIT("infix") -instance Eq Fixity where -- Used to determine if two fixities conflict - (Fixity p1 dir1) == (Fixity p2 dir2) = p1==p2 && dir1 == dir2 +------------------------ +maxPrecedence = (9::Int) +defaultFixity = Fixity maxPrecedence InfixL + +negateFixity :: Fixity +negateFixity = Fixity negatePrecedence InfixL -- Precedence of unary negate is wired in as infixl 6! + +negatePrecedence :: Int +negatePrecedence = 6 \end{code} +Consider -%************************************************************************ -%* * -\subsection[NewType/DataType]{NewType/DataType flag} -%* * -%************************************************************************ +\begin{verbatim} + a `op1` b `op2` c +\end{verbatim} +@(compareFixity op1 op2)@ tells which way to arrange appication, or +whether there's an error. \begin{code} -data NewOrData - = NewType -- "newtype Blah ..." - | DataType -- "data Blah ..." - deriving( Eq ) -- Needed because Demand derives Eq +compareFixity :: Fixity -> Fixity + -> (Bool, -- Error please + Bool) -- Associate to the right: a op1 (b op2 c) +compareFixity (Fixity prec1 dir1) (Fixity prec2 dir2) + = case prec1 `compare` prec2 of + GT -> left + LT -> right + EQ -> case (dir1, dir2) of + (InfixR, InfixR) -> right + (InfixL, InfixL) -> left + _ -> error_please + where + right = (False, True) + left = (False, False) + error_please = (True, False) \end{code} -The @RecFlag@ tells whether the thing is part of a recursive group or not. - %************************************************************************ %* * @@ -163,6 +199,18 @@ The @RecFlag@ tells whether the thing is part of a recursive group or not. data TopLevelFlag = TopLevel | NotTopLevel + +isTopLevel, isNotTopLevel :: TopLevelFlag -> Bool + +isNotTopLevel NotTopLevel = True +isNotTopLevel TopLevel = False + +isTopLevel TopLevel = True +isTopLevel NotTopLevel = False + +instance Outputable TopLevelFlag where + ppr TopLevel = ptext SLIT("") + ppr NotTopLevel = ptext SLIT("") \end{code} @@ -172,8 +220,257 @@ data TopLevelFlag %* * %************************************************************************ +\begin{code} +data Boxity + = Boxed + | Unboxed + deriving( Eq ) + +isBoxed :: Boxity -> Bool +isBoxed Boxed = True +isBoxed Unboxed = False +\end{code} + + +%************************************************************************ +%* * +\subsection[Recursive/Non-Recursive]{Recursive/Non-Recursive flag} +%* * +%************************************************************************ + \begin{code} -data RecFlag - = Recursive - | NonRecursive +data RecFlag = Recursive + | NonRecursive + deriving( Eq ) + +isRec :: RecFlag -> Bool +isRec Recursive = True +isRec NonRecursive = False + +isNonRec :: RecFlag -> Bool +isNonRec Recursive = False +isNonRec NonRecursive = True + +boolToRecFlag :: Bool -> RecFlag +boolToRecFlag True = Recursive +boolToRecFlag False = NonRecursive + +instance Outputable RecFlag where + ppr Recursive = ptext SLIT("Recursive") + ppr NonRecursive = ptext SLIT("NonRecursive") +\end{code} + +%************************************************************************ +%* * + Tuples +%* * +%************************************************************************ + +\begin{code} +data TupCon = TupCon Boxity Arity + +instance Eq TupCon where + (TupCon b1 a1) == (TupCon b2 a2) = b1==b2 && a1==a2 + +tupleParens :: Boxity -> SDoc -> SDoc +tupleParens Boxed p = parens p +tupleParens Unboxed p = ptext SLIT("(#") <+> p <+> ptext SLIT("#)") \end{code} + +%************************************************************************ +%* * +\subsection[Generic]{Generic flag} +%* * +%************************************************************************ + +This is the "Embedding-Projection pair" datatype, it contains +two pieces of code (normally either RenamedExpr's or Id's) +If we have a such a pair (EP from to), the idea is that 'from' and 'to' +represents functions of type + + from :: T -> Tring + to :: Tring -> T + +And we should have + + to (from x) = x + +T and Tring are arbitrary, but typically T is the 'main' type while +Tring is the 'representation' type. (This just helps us remember +whether to use 'from' or 'to'. + +\begin{code} +data EP a = EP { fromEP :: a, -- :: T -> Tring + toEP :: a } -- :: Tring -> T +\end{code} + +Embedding-projection pairs are used in several places: + +First of all, each type constructor has an EP associated with it, the +code in EP converts (datatype T) from T to Tring and back again. + +Secondly, when we are filling in Generic methods (in the typechecker, +tcMethodBinds), we are constructing bimaps by induction on the structure +of the type of the method signature. + + +%************************************************************************ +%* * +\subsection{Occurrence information} +%* * +%************************************************************************ + +This data type is used exclusively by the simplifier, but it appears in a +SubstResult, which is currently defined in VarEnv, which is pretty near +the base of the module hierarchy. So it seemed simpler to put the +defn of OccInfo here, safely at the bottom + +\begin{code} +data OccInfo + = NoOccInfo + + | IAmDead -- Marks unused variables. Sometimes useful for + -- lambda and case-bound variables. + + | OneOcc InsideLam + + OneBranch + + | IAmALoopBreaker -- Used by the occurrence analyser to mark loop-breakers + -- in a group of recursive definitions + +seqOccInfo :: OccInfo -> () +seqOccInfo (OneOcc in_lam once) = in_lam `seq` once `seq` () +seqOccInfo occ = () + +type InsideLam = Bool -- True <=> Occurs inside a non-linear lambda + -- Substituting a redex for this occurrence is + -- dangerous because it might duplicate work. +insideLam = True +notInsideLam = False + +type OneBranch = Bool -- True <=> Occurs in only one case branch + -- so no code-duplication issue to worry about +oneBranch = True +notOneBranch = False + +isLoopBreaker :: OccInfo -> Bool +isLoopBreaker IAmALoopBreaker = True +isLoopBreaker other = False + +isDeadOcc :: OccInfo -> Bool +isDeadOcc IAmDead = True +isDeadOcc other = False + +isOneOcc (OneOcc _ _) = True +isOneOcc other = False + +isFragileOcc :: OccInfo -> Bool +isFragileOcc (OneOcc _ _) = True +isFragileOcc other = False +\end{code} + +\begin{code} +instance Outputable OccInfo where + -- only used for debugging; never parsed. KSW 1999-07 + ppr NoOccInfo = empty + ppr IAmALoopBreaker = ptext SLIT("_Kx") + ppr IAmDead = ptext SLIT("_Kd") + ppr (OneOcc inside_lam one_branch) | inside_lam = ptext SLIT("_Kl") + | one_branch = ptext SLIT("_Ks") + | otherwise = ptext SLIT("_Ks*") + +instance Show OccInfo where + showsPrec p occ = showsPrecSDoc p (ppr occ) +\end{code} + +%************************************************************************ +%* * +\subsection{Strictness indication} +%* * +%************************************************************************ + +The strictness annotations on types in data type declarations +e.g. data T = MkT !Int !(Bool,Bool) + +\begin{code} +data StrictnessMark -- Used in interface decls only + = MarkedStrict + | MarkedUnboxed + | NotMarkedStrict + deriving( Eq ) + +isMarkedUnboxed MarkedUnboxed = True +isMarkedUnboxed other = False + +isMarkedStrict NotMarkedStrict = False +isMarkedStrict other = True -- All others are strict + +instance Outputable StrictnessMark where + ppr MarkedStrict = ptext SLIT("!") + ppr MarkedUnboxed = ptext SLIT("!!") + ppr NotMarkedStrict = ptext SLIT("_") +\end{code} + + +%************************************************************************ +%* * +\subsection{Success flag} +%* * +%************************************************************************ + +\begin{code} +data SuccessFlag = Succeeded | Failed + +successIf :: Bool -> SuccessFlag +successIf True = Succeeded +successIf False = Failed + +succeeded, failed :: SuccessFlag -> Bool +succeeded Succeeded = True +succeeded Failed = False + +failed Succeeded = False +failed Failed = True +\end{code} + + +%************************************************************************ +%* * +\subsection{Activation} +%* * +%************************************************************************ + +When a rule or inlining is active + +\begin{code} +type CompilerPhase = Int -- Compilation phase + -- Phases decrease towards zero + -- Zero is the last phase + +data Activation = NeverActive + | AlwaysActive + | ActiveBefore CompilerPhase -- Active only *before* this phase + | ActiveAfter CompilerPhase -- Active in this phase and later + deriving( Eq ) -- Eq used in comparing rules in HsDecls + +instance Outputable Activation where + ppr AlwaysActive = empty -- The default + ppr (ActiveBefore n) = brackets (char '~' <> int n) + ppr (ActiveAfter n) = brackets (int n) + ppr NeverActive = ptext SLIT("NEVER") + +isActive :: CompilerPhase -> Activation -> Bool +isActive p NeverActive = False +isActive p AlwaysActive = True +isActive p (ActiveAfter n) = p <= n +isActive p (ActiveBefore n) = p > n + +isNeverActive, isAlwaysActive :: Activation -> Bool +isNeverActive NeverActive = True +isNeverActive act = False + +isAlwaysActive AlwaysActive = True +isAlwaysActive other = False +\end{code} +