X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Fprelude%2FPrelRules.lhs;h=f9af8b09dee59a53511394e56d4a049805576b81;hb=940d9d970d9d824413f2776faf0f6cbd3f033f91;hp=0cc8c2bb903e89ffc11a39b50e1a8ce2e88a33be;hpb=abc45a98629e11d86c339cca64c3a4575b9c0f5e;p=ghc-hetmet.git diff --git a/ghc/compiler/prelude/PrelRules.lhs b/ghc/compiler/prelude/PrelRules.lhs index 0cc8c2b..f9af8b0 100644 --- a/ghc/compiler/prelude/PrelRules.lhs +++ b/ghc/compiler/prelude/PrelRules.lhs @@ -3,6 +3,10 @@ % \section[ConFold]{Constant Folder} +Conceptually, constant folding should be parameterized with the kind +of target machine to get identical behaviour during compilation time +and runtime. We cheat a little bit here... + ToDo: check boundaries before folding, e.g. we can fold the Float addition (i1 + i2) only if it results in a valid Float. @@ -13,60 +17,84 @@ module PrelRules ( primOpRule, builtinRules ) where #include "HsVersions.h" import CoreSyn -import Rules ( ProtoCoreRule(..) ) -import Id ( idUnfolding, mkWildId, isDataConId_maybe ) -import Literal ( Literal(..), isLitLitLit, mkMachInt, mkMachWord, inIntRange, literalType, - word2IntLit, int2WordLit, int2CharLit, char2IntLit, int2FloatLit, int2DoubleLit +import Id ( mkWildId ) +import Literal ( Literal(..), isLitLitLit, mkMachInt, mkMachWord + , literalType + , word2IntLit, int2WordLit, char2IntLit, int2CharLit + , float2IntLit, int2FloatLit, double2IntLit, int2DoubleLit + , addr2IntLit, int2AddrLit, float2DoubleLit, double2FloatLit ) import PrimOp ( PrimOp(..), primOpOcc ) import TysWiredIn ( trueDataConId, falseDataConId ) -import TyCon ( tyConDataCons, isEnumerationTyCon, isNewTyCon ) -import DataCon ( DataCon, dataConTag, dataConRepArity, dataConTyCon, dataConId, fIRST_TAG ) -import CoreUnfold ( maybeUnfoldingTemplate ) +import TyCon ( tyConDataConsIfAvailable, isEnumerationTyCon, isNewTyCon ) +import DataCon ( dataConTag, dataConTyCon, dataConId, fIRST_TAG ) import CoreUtils ( exprIsValue, cheapEqExpr, exprIsConApp_maybe ) -import Type ( splitTyConApp_maybe ) +import Type ( tyConAppTyCon ) import OccName ( occNameUserString) -import ThinAir ( unpackCStringFoldrId ) -import Maybes ( maybeToBool ) -import Char ( ord, chr ) +import PrelNames ( unpackCStringFoldrName, unpackCStringFoldrIdKey, hasKey ) +import Name ( Name ) +import Bits ( Bits(..) ) +#if __GLASGOW_HASKELL__ >= 500 +import Word ( Word ) +#else +import Word ( Word64 ) +#endif import Outputable +import CmdLineOpts ( opt_SimplExcessPrecision ) \end{code} - \begin{code} primOpRule :: PrimOp -> CoreRule primOpRule op = BuiltinRule (primop_rule op) where op_name = _PK_ (occNameUserString (primOpOcc op)) - op_name_case = op_name _APPEND_ SLIT("case") + op_name_case = op_name _APPEND_ SLIT("->case") -- ToDo: something for integer-shift ops? -- NotOp - -- Int2WordOp -- SIGH: these two cause trouble in unfoldery - -- Int2AddrOp -- as we can't distinguish unsigned literals in interfaces (ToDo?) primop_rule SeqOp = seqRule primop_rule TagToEnumOp = tagToEnumRule primop_rule DataToTagOp = dataToTagRule - -- Char operations - primop_rule OrdOp = oneLit (litCoerce char2IntLit op_name) - - -- Int/Word operations - primop_rule IntAddOp = twoLits (intOp2 (+) op_name) - primop_rule IntSubOp = twoLits (intOp2 (-) op_name) - primop_rule IntMulOp = twoLits (intOp2 (*) op_name) - primop_rule IntQuotOp = twoLits (intOp2Z quot op_name) - primop_rule IntRemOp = twoLits (intOp2Z rem op_name) - primop_rule IntNegOp = oneLit (negOp op_name) - - primop_rule ChrOp = oneLit (litCoerce int2CharLit op_name) - primop_rule Int2FloatOp = oneLit (litCoerce int2FloatLit op_name) - primop_rule Int2DoubleOp = oneLit (litCoerce int2DoubleLit op_name) - primop_rule Word2IntOp = oneLit (litCoerce word2IntLit op_name) - primop_rule Int2WordOp = oneLit (litCoerce int2WordLit op_name) + -- Int operations + primop_rule IntAddOp = twoLits (intOp2 (+) op_name) + primop_rule IntSubOp = twoLits (intOp2 (-) op_name) + primop_rule IntMulOp = twoLits (intOp2 (*) op_name) + primop_rule IntQuotOp = twoLits (intOp2Z quot op_name) + primop_rule IntRemOp = twoLits (intOp2Z rem op_name) + primop_rule IntNegOp = oneLit (negOp op_name) + + -- Word operations +#if __GLASGOW_HASKELL__ >= 500 + primop_rule WordAddOp = twoLits (wordOp2 (+) op_name) + primop_rule WordSubOp = twoLits (wordOp2 (-) op_name) + primop_rule WordMulOp = twoLits (wordOp2 (*) op_name) +#endif + primop_rule WordQuotOp = twoLits (wordOp2Z quot op_name) + primop_rule WordRemOp = twoLits (wordOp2Z rem op_name) +#if __GLASGOW_HASKELL__ >= 407 + primop_rule AndOp = twoLits (wordBitOp2 (.&.) op_name) + primop_rule OrOp = twoLits (wordBitOp2 (.|.) op_name) + primop_rule XorOp = twoLits (wordBitOp2 xor op_name) +#endif + + -- coercions + primop_rule Word2IntOp = oneLit (litCoerce word2IntLit op_name) + primop_rule Int2WordOp = oneLit (litCoerce int2WordLit op_name) + primop_rule OrdOp = oneLit (litCoerce char2IntLit op_name) + primop_rule ChrOp = oneLit (litCoerce int2CharLit op_name) + primop_rule Float2IntOp = oneLit (litCoerce float2IntLit op_name) + primop_rule Int2FloatOp = oneLit (litCoerce int2FloatLit op_name) + primop_rule Double2IntOp = oneLit (litCoerce double2IntLit op_name) + primop_rule Int2DoubleOp = oneLit (litCoerce int2DoubleLit op_name) + primop_rule Addr2IntOp = oneLit (litCoerce addr2IntLit op_name) + primop_rule Int2AddrOp = oneLit (litCoerce int2AddrLit op_name) + -- SUP: Not sure what the standard says about precision in the following 2 cases + primop_rule Float2DoubleOp = oneLit (litCoerce float2DoubleLit op_name) + primop_rule Double2FloatOp = oneLit (litCoerce double2FloatLit op_name) -- Float primop_rule FloatAddOp = twoLits (floatOp2 (+) op_name) @@ -80,6 +108,7 @@ primOpRule op primop_rule DoubleSubOp = twoLits (doubleOp2 (-) op_name) primop_rule DoubleMulOp = twoLits (doubleOp2 (*) op_name) primop_rule DoubleDivOp = twoLits (doubleOp2Z (/) op_name) + primop_rule DoubleNegOp = oneLit (negOp op_name) -- Relational operators primop_rule IntEqOp = relop (==) `or_rule` litEq True op_name_case @@ -166,18 +195,38 @@ cmpOp cmp name l1 l2 negOp name (MachFloat f) = Just (name, mkFloatVal (-f)) negOp name (MachDouble d) = Just (name, mkDoubleVal (-d)) -negOp name l@(MachInt i) = intResult name (ppr l) (-i) +negOp name (MachInt i) = intResult name (-i) negOp name l = Nothing -------------------------- -intOp2 op name l1@(MachInt i1) l2@(MachInt i2) - = intResult name (ppr l1 <+> ppr l2) (i1 `op` i2) +intOp2 op name (MachInt i1) (MachInt i2) + = intResult name (i1 `op` i2) intOp2 op name l1 l2 = Nothing -- Could find LitLit intOp2Z op name (MachInt i1) (MachInt i2) | i2 /= 0 = Just (name, mkIntVal (i1 `op` i2)) intOp2Z op name l1 l2 = Nothing -- LitLit or zero dividend +-------------------------- +#if __GLASGOW_HASKELL__ >= 500 +wordOp2 op name (MachWord w1) (MachWord w2) + = wordResult name (w1 `op` w2) +wordOp2 op name l1 l2 = Nothing -- Could find LitLit +#endif + +wordOp2Z op name (MachWord w1) (MachWord w2) + | w2 /= 0 = Just (name, mkWordVal (w1 `op` w2)) +wordOp2Z op name l1 l2 = Nothing -- LitLit or zero dividend + +#if __GLASGOW_HASKELL__ >= 500 +wordBitOp2 op name l1@(MachWord w1) l2@(MachWord w2) + = Just (name, mkWordVal (w1 `op` w2)) +#else +-- Integer is not an instance of Bits, so we operate on Word64 +wordBitOp2 op name l1@(MachWord w1) l2@(MachWord w2) + = Just (name, mkWordVal ((fromIntegral::Word64->Integer) (fromIntegral w1 `op` fromIntegral w2))) +#endif +wordBitOp2 op name l1 l2 = Nothing -- Could find LitLit -------------------------- floatOp2 op name (MachFloat f1) (MachFloat f2) @@ -185,18 +234,16 @@ floatOp2 op name (MachFloat f1) (MachFloat f2) floatOp2 op name l1 l2 = Nothing floatOp2Z op name (MachFloat f1) (MachFloat f2) - | f1 /= 0 = Just (name, mkFloatVal (f1 `op` f2)) + | f2 /= 0 = Just (name, mkFloatVal (f1 `op` f2)) floatOp2Z op name l1 l2 = Nothing - - -------------------------- doubleOp2 op name (MachDouble f1) (MachDouble f2) = Just (name, mkDoubleVal (f1 `op` f2)) doubleOp2 op name l1 l2 = Nothing doubleOp2Z op name (MachDouble f1) (MachDouble f2) - | f1 /= 0 = Just (name, mkDoubleVal (f1 `op` f2)) + | f2 /= 0 = Just (name, mkDoubleVal (f1 `op` f2)) doubleOp2Z op name l1 l2 = Nothing @@ -237,19 +284,20 @@ do_lit_eq is_eq name lit expr val_if_neq | is_eq = falseVal | otherwise = trueVal -intResult name pp_args result - | not (inIntRange result) - -- Better tell the user that we've overflowed... - -- ..not that it stops us from actually folding! - - = pprTrace "Warning:" (text "Integer overflow in:" <+> ppr name <+> pp_args) - Just (name, mkIntVal (squash result)) - - | otherwise - = Just (name, mkIntVal result) - -squash :: Integer -> Integer -- Squash into Int range -squash i = toInteger ((fromInteger i)::Int) +-- Note that we *don't* warn the user about overflow. It's not done at +-- runtime either, and compilation of completely harmless things like +-- ((124076834 :: Word32) + (2147483647 :: Word32)) +-- would yield a warning. Instead we simply squash the value into the +-- Int range, but not in a way suitable for cross-compiling... :-( +intResult :: RuleName -> Integer -> Maybe (RuleName, CoreExpr) +intResult name result + = Just (name, mkIntVal (toInteger (fromInteger result :: Int))) + +#if __GLASGOW_HASKELL__ >= 500 +wordResult :: RuleName -> Integer -> Maybe (RuleName, CoreExpr) +wordResult name result + = Just (name, mkWordVal (toInteger (fromInteger result :: Word))) +#endif \end{code} @@ -263,25 +311,33 @@ squash i = toInteger ((fromInteger i)::Int) type RuleFun = [CoreExpr] -> Maybe (RuleName, CoreExpr) or_rule :: RuleFun -> RuleFun -> RuleFun -or_rule r1 r2 args = case r1 args of - Just stuff -> Just stuff - Nothing -> r2 args +or_rule r1 r2 args = maybe (r2 args) Just (r1 args) -- i.e.: r1 args `mplus` r2 args twoLits :: (Literal -> Literal -> Maybe (RuleName, CoreExpr)) -> RuleFun -twoLits rule [Lit l1, Lit l2] = rule l1 l2 +twoLits rule [Lit l1, Lit l2] = rule (convFloating l1) (convFloating l2) twoLits rule other = Nothing oneLit :: (Literal -> Maybe (RuleName, CoreExpr)) -> RuleFun -oneLit rule [Lit l1] = rule l1 +oneLit rule [Lit l1] = rule (convFloating l1) oneLit rule other = Nothing +-- When excess precision is not requested, cut down the precision of the +-- Rational value to that of Float/Double. We confuse host architecture +-- and target architecture here, but it's convenient (and wrong :-). +convFloating :: Literal -> Literal +convFloating (MachFloat f) | not opt_SimplExcessPrecision = + MachFloat (toRational ((fromRational f) :: Float )) +convFloating (MachDouble d) | not opt_SimplExcessPrecision = + MachDouble (toRational ((fromRational d) :: Double)) +convFloating l = l + trueVal = Var trueDataConId falseVal = Var falseDataConId -mkIntVal i = Lit (mkMachInt i) -mkCharVal c = Lit (MachChar c) -mkFloatVal f = Lit (MachFloat f) -mkDoubleVal d = Lit (MachDouble d) +mkIntVal i = Lit (mkMachInt i) +mkWordVal w = Lit (mkMachWord w) +mkFloatVal f = Lit (convFloating (MachFloat f)) +mkDoubleVal d = Lit (convFloating (MachDouble d)) \end{code} @@ -354,12 +410,16 @@ seqRule other = Nothing \begin{code} tagToEnumRule [Type ty, Lit (MachInt i)] = ASSERT( isEnumerationTyCon tycon ) - Just (SLIT("TagToEnum"), Var (dataConId dc)) + case filter correct_tag (tyConDataConsIfAvailable tycon) of + + + [] -> Nothing -- Abstract type + (dc:rest) -> ASSERT( null rest ) + Just (SLIT("TagToEnum"), Var (dataConId dc)) where - tag = fromInteger i - constrs = tyConDataCons tycon - (dc:_) = [ dc | dc <- constrs, tag == dataConTag dc - fIRST_TAG ] - (Just (tycon,_)) = splitTyConApp_maybe ty + correct_tag dc = (dataConTag dc - fIRST_TAG) == tag + tag = fromInteger i + tycon = tyConAppTyCon ty tagToEnumRule other = Nothing \end{code} @@ -388,15 +448,15 @@ dataToTagRule other = Nothing %************************************************************************ \begin{code} -builtinRules :: [ProtoCoreRule] +builtinRules :: [(Name, CoreRule)] -- Rules for non-primops that can't be expressed using a RULE pragma builtinRules - = [ ProtoCoreRule False unpackCStringFoldrId - (BuiltinRule match_append_lit_str) + = [ (unpackCStringFoldrName, BuiltinRule match_append_lit_str) ] --- unpack "foo" c (unpack "baz" c n) = unpack "foobaz" c n +-- The rule is this: +-- unpackFoldrCString# "foo" c (unpackFoldrCString# "baz" c n) = unpackFoldrCString# "foobaz" c n match_append_lit_str [Type ty1, Lit (MachStr s1), @@ -406,7 +466,7 @@ match_append_lit_str [Type ty1, `App` c2 `App` n ] - | unpk == unpackCStringFoldrId && + | unpk `hasKey` unpackCStringFoldrIdKey && c1 `cheapEqExpr` c2 = ASSERT( ty1 == ty2 ) Just (SLIT("AppendLitString"),