%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1995
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
%
%************************************************************************
%* *
Convert a @CoreSyntax@ program to a @StgSyntax@ program.
-
\begin{code}
-#include "HsVersions.h"
+module CoreToStg ( topCoreBindsToStg ) where
-module CoreToStg (
- topCoreBindsToStg,
-
- -- and to make the interface self-sufficient...
- SplitUniqSupply, Id, CoreExpr, CoreBinding, StgBinding,
- StgRhs, StgBinderInfo
- ) where
+#include "HsVersions.h"
-import PlainCore -- input
-import AnnCoreSyn -- intermediate form on which all work is done
+import CoreSyn -- input
import StgSyn -- output
-import SplitUniq
-import Unique -- the UniqueSupply monadery used herein
-import AbsPrel ( unpackCStringId, unpackCString2Id, stringTy,
- integerTy, rationalTy, ratioDataCon,
- PrimOp(..), -- For Int2IntegerOp etc
+import Bag ( emptyBag, unitBag, unionBags, unionManyBags, bagToList )
+import CoreUtils ( coreExprType )
+import CostCentre ( noCostCentre )
+import MkId ( mkSysLocal )
+import Id ( idType, isBottomingId,
+ externallyVisibleId, mkIdWithNewUniq,
+ nullIdEnv, addOneToIdEnv, lookupIdEnv, growIdEnvList,
+ IdEnv, Id
+ )
+import Literal ( mkMachInt, Literal(..) )
+import PrelVals ( unpackCStringId, unpackCString2Id,
integerZeroId, integerPlusOneId,
integerPlusTwoId, integerMinusOneId
- IF_ATTACK_PRAGMAS(COMMA mkListTy COMMA charTy)
- IF_ATTACK_PRAGMAS(COMMA tagOf_PrimOp)
- IF_ATTACK_PRAGMAS(COMMA pprPrimOp)
- )
-
-import AbsUniType ( isPrimType, isLeakFreeType, getUniDataTyCon )
-import Bag -- Bag operations
-import BasicLit ( mkMachInt, BasicLit(..), PrimKind ) -- ToDo: its use is ugly...
-import CostCentre ( noCostCentre, CostCentre )
-import Id ( mkSysLocal, getIdUniType, isBottomingId
- IF_ATTACK_PRAGMAS(COMMA bottomIsGuaranteed)
)
-import IdEnv
-import Maybes ( Maybe(..), catMaybes )
-import Outputable ( isExported )
-import Pretty -- debugging only!
-import SpecTyFuns ( mkSpecialisedCon )
-import SrcLoc ( SrcLoc, mkUnknownSrcLoc )
-import Util
+import PrimOp ( PrimOp(..) )
+import SrcLoc ( noSrcLoc )
+import TyCon ( TyCon{-instance Uniquable-} )
+import Type ( splitAlgTyConApp, Type )
+import TysWiredIn ( stringTy )
+import Unique ( integerTyConKey, ratioTyConKey, Unique{-instance Eq-} )
+import UniqSupply -- all of it, really
+import Util ( zipLazy )
+import Outputable
+import Ratio ( numerator, denominator )
+
+isLeakFreeType x y = False -- safe option; ToDo
\end{code}
x = y t1 t2
where t1, t2 are types
-* We make the representation of NoRep literals explicit, and
- float their bindings to the top level
+* We don't pin on correct arities any more, because they can be mucked up
+ by the lambda lifter. In particular, the lambda lifter can take a local
+ letrec-bound variable and make it a lambda argument, which shouldn't have
+ an arity. So SetStgVarInfo sets arities now.
* We do *not* pin on the correct free/live var info; that's done later.
Instead we use bOGUS_LVS and _FVS as a placeholder.
-* We convert case x of {...; x' -> ...x'...}
- to
- case x of {...; _ -> ...x... }
-
- See notes in SimplCase.lhs, near simplDefault for the reasoning here.
+[Quite a bit of stuff that used to be here has moved
+ to tidyCorePgm (SimplCore.lhs) SLPJ Nov 96]
%************************************************************************
environment, so we can just replace all occurrences of \tr{x}
with \tr{y}.
+March 98: We also use this environment to give all locally bound
+Names new unique ids, since the code generator assumes that binders
+are unique across a module. (Simplifier doesn't maintain this
+invariant any longer.)
+
\begin{code}
-type StgEnv = IdEnv PlainStgAtom
+type StgEnv = IdEnv StgArg
\end{code}
No free/live variable information is pinned on in this pass; it's added
we use @bOGUS_LVs@ and @bOGUS_FVs@ as placeholders.
\begin{code}
-bOGUS_LVs :: PlainStgLiveVars
+bOGUS_LVs :: StgLiveVars
bOGUS_LVs = panic "bOGUS_LVs" -- emptyUniqSet (used when pprTracing)
bOGUS_FVs :: [Id]
\end{code}
\begin{code}
-topCoreBindsToStg :: SplitUniqSupply -- name supply
- -> [PlainCoreBinding] -- input
- -> [PlainStgBinding] -- output
+topCoreBindsToStg :: UniqSupply -- name supply
+ -> [CoreBinding] -- input
+ -> [StgBinding] -- output
topCoreBindsToStg us core_binds
- = case (initSUs us (binds_to_stg nullIdEnv core_binds)) of
- (_, stuff) -> stuff
+ = initUs us (coreBindsToStg nullIdEnv core_binds)
where
- binds_to_stg :: StgEnv -> [PlainCoreBinding] -> SUniqSM [PlainStgBinding]
-
- binds_to_stg env [] = returnSUs []
- binds_to_stg env (b:bs)
- = do_top_bind env b `thenSUs` \ (new_b, new_env, float_binds) ->
- binds_to_stg new_env bs `thenSUs` \ new_bs ->
- returnSUs (bagToList float_binds ++ -- Literals
- new_b ++
- new_bs)
-
- do_top_bind env bind@(CoRec pairs)
- = coreBindToStg env bind
-
- do_top_bind env bind@(CoNonRec var rhs)
- = coreBindToStg env bind `thenSUs` \ (stg_binds, new_env, float_binds) ->
-{- TESTING:
- let
- ppr_blah xs = ppInterleave ppComma (map pp_x xs)
- pp_x (u,x) = ppBesides [pprUnique u, ppStr ": ", ppr PprDebug x]
- in
- pprTrace "do_top_bind:" (ppAbove (ppr PprDebug stg_binds) (ppr_blah (ufmToList new_env))) $
--}
- case stg_binds of
- [StgNonRec var (StgRhsClosure cc bi fvs u [] rhs_body)] ->
- -- Mega-special case; there's still a binding there
- -- no fvs (of course), *no args*, "let" rhs
- let
- (extra_float_binds, rhs_body') = seek_liftable [] rhs_body
- in
- returnSUs (extra_float_binds ++
- [StgNonRec var (StgRhsClosure cc bi fvs u [] rhs_body')],
- new_env,
- float_binds)
-
- other -> returnSUs (stg_binds, new_env, float_binds)
-
- --------------------
- -- HACK: look for very simple, obviously-liftable bindings
- -- that can come up to the top level; those that couldn't
- -- 'cause they were big-lambda constrained in the Core world.
-
- seek_liftable :: [PlainStgBinding] -- accumulator...
- -> PlainStgExpr -- look for top-lev liftables
- -> ([PlainStgBinding], PlainStgExpr) -- result
-
- seek_liftable acc expr@(StgLet inner_bind body)
- | is_liftable inner_bind
- = seek_liftable (inner_bind : acc) body
-
- seek_liftable acc other_expr = (reverse acc, other_expr) -- Finished
-
- --------------------
- is_liftable (StgNonRec binder (StgRhsClosure _ _ _ _ args body))
- = not (null args) -- it's manifestly a function...
- || isLeakFreeType [] (getIdUniType binder)
- || is_whnf body
- -- ToDo: use a decent manifestlyWHNF function for STG?
- where
- is_whnf (StgConApp _ _ _) = True
- is_whnf (StgApp (StgVarAtom v) _ _) = isBottomingId v
- is_whnf other = False
-
- is_liftable (StgRec [(_, StgRhsClosure _ _ _ _ args body)])
- = not (null args) -- it's manifestly a (recursive) function...
+ coreBindsToStg :: StgEnv -> [CoreBinding] -> UniqSM [StgBinding]
- is_liftable anything_else = False
+ coreBindsToStg env [] = returnUs []
+ coreBindsToStg env (b:bs)
+ = coreBindToStg env b `thenUs` \ (new_b, new_env) ->
+ coreBindsToStg new_env bs `thenUs` \ new_bs ->
+ returnUs (new_b ++ new_bs)
\end{code}
%************************************************************************
\begin{code}
coreBindToStg :: StgEnv
- -> PlainCoreBinding
- -> SUniqSM ([PlainStgBinding], -- Empty or singleton
- StgEnv, -- New envt
- Bag PlainStgBinding) -- Floats
-
-coreBindToStg env (CoNonRec binder rhs)
- = coreRhsToStg env rhs `thenSUs` \ (stg_rhs, rhs_binds) ->
+ -> CoreBinding
+ -> UniqSM ([StgBinding], -- Empty or singleton
+ StgEnv) -- Floats
+coreBindToStg env (NonRec binder rhs)
+ = coreRhsToStg env rhs `thenUs` \ stg_rhs ->
let
-- Binds to return if RHS is trivial
- triv_binds = if isExported binder then
- [StgNonRec binder stg_rhs] -- Retain it
- else
- [] -- Discard it
+ triv_binds | externallyVisibleId binder = [StgNonRec binder stg_rhs] -- Retain it
+ | otherwise = [] -- Discard it
in
case stg_rhs of
- StgRhsClosure cc bi fvs upd [] (StgApp atom [] lvs) ->
+ StgRhsClosure cc bi fvs upd [] (StgApp atom [] lvs) ->
-- Trivial RHS, so augment envt, and ditch the binding
- returnSUs (triv_binds, new_env, rhs_binds)
+ returnUs (triv_binds, new_env)
where
new_env = addOneToIdEnv env binder atom
-
- StgRhsCon cc con_id [] ->
+
+ StgRhsCon cc con_id [] ->
-- Trivial RHS, so augment envt, and ditch the binding
- returnSUs (triv_binds, new_env, rhs_binds)
+ returnUs (triv_binds, new_env)
where
- new_env = addOneToIdEnv env binder (StgVarAtom con_id)
-
- other -> -- Non-trivial RHS, so don't augment envt
- returnSUs ([StgNonRec binder stg_rhs], env, rhs_binds)
-
-coreBindToStg env (CoRec pairs)
+ new_env = addOneToIdEnv env binder (StgConArg con_id)
+
+ other -> -- Non-trivial RHS
+ mkUniqueBinder env binder `thenUs` \ (new_env, new_binder) ->
+ returnUs ([StgNonRec new_binder stg_rhs], new_env)
+ where
+ mkUniqueBinder env binder
+ | externallyVisibleId binder = returnUs (env, binder)
+ | otherwise =
+ -- local binder, give it a new unique Id.
+ newUniqueLocalId binder `thenUs` \ binder' ->
+ let
+ new_env = addOneToIdEnv env binder (StgVarArg binder')
+ in
+ returnUs (new_env, binder')
+
+
+coreBindToStg env (Rec pairs)
= -- NB: *** WE DO NOT CHECK FOR TRIV_BINDS in REC BIND ****
-- (possibly ToDo)
let
(binders, rhss) = unzip pairs
in
- mapAndUnzipSUs (coreRhsToStg env) rhss `thenSUs` \ (stg_rhss, rhs_binds) ->
- returnSUs ([StgRec (binders `zip` stg_rhss)], env, unionManyBags rhs_binds)
+ newLocalIds env True{-maybe externally visible-} binders `thenUs` \ (binders', env') ->
+ mapUs (coreRhsToStg env') rhss `thenUs` \ stg_rhss ->
+ returnUs ([StgRec (binders' `zip` stg_rhss)], env')
\end{code}
%************************************************************************
\begin{code}
-coreRhsToStg :: StgEnv -> PlainCoreExpr -> SUniqSM (PlainStgRhs, Bag PlainStgBinding)
+coreRhsToStg :: StgEnv -> CoreExpr -> UniqSM StgRhs
coreRhsToStg env core_rhs
- = coreExprToStg env core_rhs `thenSUs` \ (stg_expr, stg_binds) ->
+ = coreExprToStg env core_rhs `thenUs` \ stg_expr ->
let stg_rhs = case stg_expr of
- StgLet (StgNonRec var1 rhs) (StgApp (StgVarAtom var2) [] _)
+ StgLet (StgNonRec var1 rhs) (StgApp (StgVarArg var2) [] _)
| var1 == var2 -> rhs
-- This curious stuff is to unravel what a lambda turns into
-- We have to do it this way, rather than spot a lambda in the
- -- incoming rhs
+ -- incoming rhs. Why? Because trivial bindings might conceal
+ -- what the rhs is actually like.
- StgConApp con args _ -> StgRhsCon noCostCentre con args
+ StgCon con args _ -> StgRhsCon noCostCentre con args
other -> StgRhsClosure noCostCentre -- No cost centre (ToDo?)
stgArgOcc -- safe
- bOGUS_FVs
- Updatable -- Be pessimistic
- []
- stg_expr
- in
- returnSUs (stg_rhs, stg_binds)
-\end{code}
-
-
-%************************************************************************
-%* *
-\subsection[coreToStg-lits]{Converting literals}
-%* *
-%************************************************************************
-
-Literals: the NoRep kind need to be de-no-rep'd.
-We always replace them with a simple variable, and float a suitable
-binding out to the top level.
-
-If an Integer is small enough (Haskell implementations must support
-Ints in the range $[-2^29+1, 2^29-1]$), wrap it up in @int2Integer@;
-otherwise, wrap with @litString2Integer@.
-
-\begin{code}
-tARGET_MIN_INT, tARGET_MAX_INT :: Integer
-tARGET_MIN_INT = -536870912
-tARGET_MAX_INT = 536870912
-
-litToStgAtom :: BasicLit -> SUniqSM (PlainStgAtom, Bag PlainStgBinding)
-
-litToStgAtom (NoRepStr s)
- = newStgVar stringTy `thenSUs` \ var ->
- let
- rhs = StgRhsClosure noCostCentre -- No cost centre (ToDo?)
- stgArgOcc -- safe
- bOGUS_FVs
- Updatable -- OLD: ReEntrant (see note below)
- [] -- No arguments
- val
-
--- We used not to update strings, so that they wouldn't clog up the heap,
--- but instead be unpacked each time. But on some programs that costs a lot
--- [eg hpg], so now we update them.
-
- val = if (any is_NUL (_UNPK_ s)) then -- must cater for NULs in literal string
- StgApp (StgVarAtom unpackCString2Id)
- [StgLitAtom (MachStr s),
- StgLitAtom (mkMachInt (toInteger (_LENGTH_ s)))]
- bOGUS_LVs
- else
- StgApp (StgVarAtom unpackCStringId)
- [StgLitAtom (MachStr s)]
- bOGUS_LVs
- in
- returnSUs (StgVarAtom var, unitBag (StgNonRec var rhs))
- where
- is_NUL c = c == '\0'
-
-litToStgAtom (NoRepInteger i)
- -- extremely convenient to look out for a few very common
- -- Integer literals!
- | i == 0 = returnSUs (StgVarAtom integerZeroId, emptyBag)
- | i == 1 = returnSUs (StgVarAtom integerPlusOneId, emptyBag)
- | i == 2 = returnSUs (StgVarAtom integerPlusTwoId, emptyBag)
- | i == (-1) = returnSUs (StgVarAtom integerMinusOneId, emptyBag)
-
- | otherwise
- = newStgVar integerTy `thenSUs` \ var ->
- let
- rhs = StgRhsClosure noCostCentre -- No cost centre (ToDo?)
- stgArgOcc -- safe
- bOGUS_FVs
- Updatable -- Update an integer
- [] -- No arguments
- val
-
- val
- | i > tARGET_MIN_INT && i < tARGET_MAX_INT
- = -- Start from an Int
- StgPrimApp Int2IntegerOp [StgLitAtom (mkMachInt i)] bOGUS_LVs
-
- | otherwise
- = -- Start from a string
- StgPrimApp Addr2IntegerOp [StgLitAtom (MachStr (_PK_ (show i)))] bOGUS_LVs
+ bOGUS_FVs
+ Updatable -- Be pessimistic
+ []
+ stg_expr
in
- returnSUs (StgVarAtom var, unitBag (StgNonRec var rhs))
-
-litToStgAtom (NoRepRational r)
- = litToStgAtom (NoRepInteger (numerator r)) `thenSUs` \ (num_atom, binds1) ->
- litToStgAtom (NoRepInteger (denominator r)) `thenSUs` \ (denom_atom, binds2) ->
- newStgVar rationalTy `thenSUs` \ var ->
- let
- rhs = StgRhsCon noCostCentre -- No cost centre (ToDo?)
- ratioDataCon -- Constructor
- [num_atom, denom_atom]
- in
- returnSUs (StgVarAtom var, binds1 `unionBags`
- binds2 `unionBags`
- unitBag (StgNonRec var rhs))
-
-litToStgAtom other_lit = returnSUs (StgLitAtom other_lit, emptyBag)
+ returnUs stg_rhs
\end{code}
%************************************************************************
\begin{code}
-coreAtomToStg :: StgEnv -> PlainCoreAtom -> SUniqSM (PlainStgAtom, Bag PlainStgBinding)
-
-coreAtomToStg env (CoVarAtom var) = returnSUs (stgLookup env var, emptyBag)
-coreAtomToStg env (CoLitAtom lit) = litToStgAtom lit
+coreArgsToStg :: StgEnv -> [CoreArg] -> ([Type], [StgArg])
+
+coreArgsToStg env [] = ([], [])
+coreArgsToStg env (a:as)
+ = case a of
+ TyArg t -> (t:trest, vrest)
+ VarArg v -> (trest, stgLookup env v : vrest)
+ LitArg l -> (trest, StgLitArg l : vrest)
+ where
+ (trest,vrest) = coreArgsToStg env as
\end{code}
-There's not anything interesting we can ASSERT about \tr{var} if it
-isn't in the StgEnv. (WDP 94/06)
-\begin{code}
-stgLookup :: StgEnv -> Id -> PlainStgAtom
-
-stgLookup env var = case (lookupIdEnv env var) of
- Nothing -> StgVarAtom var
- Just atom -> atom
-\end{code}
%************************************************************************
%* *
%************************************************************************
\begin{code}
-coreExprToStg :: StgEnv
- -> PlainCoreExpr
- -> SUniqSM (PlainStgExpr, -- Result
- Bag PlainStgBinding) -- Float these to top level
-\end{code}
+coreExprToStg :: StgEnv -> CoreExpr -> UniqSM StgExpr
-\begin{code}
-coreExprToStg env (CoLit lit)
- = litToStgAtom lit `thenSUs` \ (atom, binds) ->
- returnSUs (StgApp atom [] bOGUS_LVs, binds)
-
-coreExprToStg env (CoVar var)
- = returnSUs (StgApp (stgLookup env var) [] bOGUS_LVs, emptyBag)
-
-coreExprToStg env (CoCon con types args)
- = mapAndUnzipSUs (coreAtomToStg env) args `thenSUs` \ (stg_atoms, stg_binds) ->
- returnSUs (StgConApp spec_con stg_atoms bOGUS_LVs, unionManyBags stg_binds)
- where
- spec_con = mkSpecialisedCon con types
+coreExprToStg env (Lit lit)
+ = returnUs (StgApp (StgLitArg lit) [] bOGUS_LVs)
-coreExprToStg env (CoPrim op tys args)
- = mapAndUnzipSUs (coreAtomToStg env) args `thenSUs` \ (stg_atoms, stg_binds) ->
- returnSUs (StgPrimApp op stg_atoms bOGUS_LVs, unionManyBags stg_binds)
-\end{code}
+coreExprToStg env (Var var)
+ = returnUs (mk_app (stgLookup env var) [])
-%************************************************************************
-%* *
-\subsubsection[coreToStg-type-stuff]{Type application and abstraction}
-%* *
-%************************************************************************
-
-This type information dies in this Core-to-STG translation.
+coreExprToStg env (Con con args)
+ = let
+ (types, stg_atoms) = coreArgsToStg env args
+ in
+ returnUs (StgCon con stg_atoms bOGUS_LVs)
-\begin{code}
-coreExprToStg env (CoTyLam tyvar expr) = coreExprToStg env expr
-coreExprToStg env (CoTyApp expr ty) = coreExprToStg env expr
+coreExprToStg env (Prim op args)
+ = let
+ (types, stg_atoms) = coreArgsToStg env args
+ in
+ returnUs (StgPrim op stg_atoms bOGUS_LVs)
\end{code}
%************************************************************************
%************************************************************************
\begin{code}
-coreExprToStg env expr@(CoLam binders body)
- = coreExprToStg env body `thenSUs` \ (stg_body, binds) ->
- newStgVar (typeOfCoreExpr expr) `thenSUs` \ var ->
- returnSUs (StgLet (StgNonRec var (StgRhsClosure noCostCentre
- stgArgOcc
- bOGUS_FVs
- ReEntrant -- binders is non-empty
- binders
- stg_body))
- (StgApp (StgVarAtom var) [] bOGUS_LVs),
- binds)
+coreExprToStg env expr@(Lam _ _)
+ = let
+ (_, binders, body) = collectBinders expr
+ in
+ newLocalIds env False{-all local-} binders `thenUs` \ (binders', env') ->
+ coreExprToStg env' body `thenUs` \ stg_body ->
+
+ if null binders then -- it was all type/usage binders; tossed
+ returnUs stg_body
+ else
+ newStgVar (coreExprType expr) `thenUs` \ var ->
+ returnUs
+ (StgLet (StgNonRec var
+ (StgRhsClosure noCostCentre
+ stgArgOcc
+ bOGUS_FVs
+ ReEntrant -- binders is non-empty
+ binders'
+ stg_body))
+ (StgApp (StgVarArg var) [] bOGUS_LVs))
\end{code}
%************************************************************************
%************************************************************************
\begin{code}
-coreExprToStg env expr@(CoApp _ _)
- = -- Deal with the arguments
- mapAndUnzipSUs (coreAtomToStg env) args `thenSUs` \ (stg_args, arg_binds) ->
-
+coreExprToStg env expr@(App _ _)
+ = let
+ (fun,args) = collect_args expr []
+ (_, stg_args) = coreArgsToStg env args
+ in
-- Now deal with the function
- case fun of
- CoVar fun_id -> returnSUs (StgApp (stgLookup env fun_id) stg_args bOGUS_LVs,
- unionManyBags arg_binds)
+ case (fun, args) of
+ (Var fun_id, _) -> -- A function Id, so do an StgApp; it's ok if
+ -- there are no arguments.
+ returnUs (mk_app (stgLookup env fun_id) stg_args)
+
+ (non_var_fun, []) -> -- No value args, so recurse into the function
+ coreExprToStg env non_var_fun
other -> -- A non-variable applied to things; better let-bind it.
- newStgVar (typeOfCoreExpr fun) `thenSUs` \ fun_id ->
- coreExprToStg env fun `thenSUs` \ (stg_fun, fun_binds) ->
+ newStgVar (coreExprType fun) `thenUs` \ fun_id ->
+ coreExprToStg env fun `thenUs` \ (stg_fun) ->
let
fun_rhs = StgRhsClosure noCostCentre -- No cost centre (ToDo?)
stgArgOcc
[]
stg_fun
in
- returnSUs (StgLet (StgNonRec fun_id fun_rhs)
- (StgApp (StgVarAtom fun_id) stg_args bOGUS_LVs),
- unionManyBags arg_binds `unionBags`
- fun_binds)
+ returnUs (StgLet (StgNonRec fun_id fun_rhs)
+ (StgApp (StgVarArg fun_id) stg_args bOGUS_LVs))
where
- (fun,args) = collect_args expr []
-
- -- Collect arguments, discarding type applications
- collect_args (CoApp fun arg) args = collect_args fun (arg:args)
- collect_args (CoTyApp e t) args = collect_args e args
- collect_args fun args = (fun, args)
+ -- Collect arguments, discarding type/usage applications
+ collect_args (App e (TyArg _)) args = collect_args e args
+ collect_args (App fun arg) args = collect_args fun (arg:args)
+ collect_args (Note (Coerce _ _) expr) args = collect_args expr args
+ collect_args (Note InlineCall expr) args = collect_args expr args
+ collect_args fun args = (fun, args)
\end{code}
%************************************************************************
%* *
%************************************************************************
-At this point, we *mangle* cases involving fork# and par# in the
-discriminant. The original templates for these primops (see
-@PrelVals.lhs@) constructed case expressions with boolean results
-solely to fool the strictness analyzer, the simplifier, and anyone
-else who might want to fool with the evaluation order. Now, we
-believe that once the translation to STG code is performed, our
-evaluation order is safe. Therefore, we convert expressions of the
-form:
- case par# e of
- True -> rhs
- False -> parError#
+******* TO DO TO DO: fix what follows
-to
+Special case for
- case par# e of
- _ -> rhs
+ case (op x1 ... xn) of
+ y -> e
-\begin{code}
+where the type of the case scrutinee is a multi-constuctor algebraic type.
+Then we simply compile code for
-coreExprToStg env (CoCase discrim@(CoPrim op tys args) alts)
- | funnyParallelOp op =
- getSUnique `thenSUs` \ uniq ->
- coreExprToStg env discrim `thenSUs` \ (stg_discrim, discrim_binds) ->
- alts_to_stg alts `thenSUs` \ (stg_alts, alts_binds) ->
- returnSUs (
- StgCase stg_discrim
- bOGUS_LVs
- bOGUS_LVs
- uniq
- stg_alts,
- discrim_binds `unionBags` alts_binds
- )
- where
- funnyParallelOp SeqOp = True
- funnyParallelOp ParOp = True
- funnyParallelOp ForkOp = True
- funnyParallelOp _ = False
-
- discrim_ty = typeOfCoreExpr discrim
-
- alts_to_stg (CoPrimAlts _ (CoBindDefault binder rhs))
- = coreExprToStg env rhs `thenSUs` \ (stg_rhs, rhs_binds) ->
- let
- stg_deflt = StgBindDefault binder False stg_rhs
- in
- returnSUs (StgPrimAlts discrim_ty [] stg_deflt, rhs_binds)
-
--- OK, back to real life...
-
-coreExprToStg env (CoCase discrim alts)
- = coreExprToStg env discrim `thenSUs` \ (stg_discrim, discrim_binds) ->
- alts_to_stg discrim alts `thenSUs` \ (stg_alts, alts_binds) ->
- getSUnique `thenSUs` \ uniq ->
- returnSUs (
+ let y = op x1 ... xn
+ in
+ e
+
+In this case:
+
+ case (op x1 ... xn) of
+ C a b -> ...
+ y -> e
+
+where the type of the case scrutinee is a multi-constuctor algebraic type.
+we just bomb out at the moment. It never happens in practice.
+
+**** END OF TO DO TO DO
+
+\begin{code}
+coreExprToStg env (Case scrut@(Prim op args) (AlgAlts alts (BindDefault binder rhs)))
+ = if not (null alts) then
+ panic "cgCase: case on PrimOp with default *and* alts\n"
+ -- For now, die if alts are non-empty
+ else
+ coreExprToStg env (Let (NonRec binder scrut) rhs)
+
+coreExprToStg env (Case discrim alts)
+ = coreExprToStg env discrim `thenUs` \ stg_discrim ->
+ alts_to_stg discrim alts `thenUs` \ stg_alts ->
+ getUnique `thenUs` \ uniq ->
+ returnUs (
StgCase stg_discrim
bOGUS_LVs
bOGUS_LVs
uniq
- stg_alts,
- discrim_binds `unionBags` alts_binds
+ stg_alts
)
where
- discrim_ty = typeOfCoreExpr discrim
- (_, discrim_ty_args, _) = getUniDataTyCon discrim_ty
-
- alts_to_stg discrim (CoAlgAlts alts deflt)
- = default_to_stg discrim deflt `thenSUs` \ (stg_deflt, deflt_binds) ->
- mapAndUnzipSUs boxed_alt_to_stg alts `thenSUs` \ (stg_alts, alts_binds) ->
- returnSUs (StgAlgAlts discrim_ty stg_alts stg_deflt,
- deflt_binds `unionBags` unionManyBags alts_binds)
+ discrim_ty = coreExprType discrim
+ (_, discrim_ty_args, _) = splitAlgTyConApp discrim_ty
+
+ alts_to_stg discrim (AlgAlts alts deflt)
+ = default_to_stg discrim deflt `thenUs` \ stg_deflt ->
+ mapUs boxed_alt_to_stg alts `thenUs` \ stg_alts ->
+ returnUs (StgAlgAlts discrim_ty stg_alts stg_deflt)
where
boxed_alt_to_stg (con, bs, rhs)
- = coreExprToStg env rhs `thenSUs` \ (stg_rhs, rhs_binds) ->
- returnSUs ((spec_con, bs, [ True | b <- bs ]{-bogus use mask-}, stg_rhs),
- rhs_binds)
- where
- spec_con = mkSpecialisedCon con discrim_ty_args
-
- alts_to_stg discrim (CoPrimAlts alts deflt)
- = default_to_stg discrim deflt `thenSUs` \ (stg_deflt,deflt_binds) ->
- mapAndUnzipSUs unboxed_alt_to_stg alts `thenSUs` \ (stg_alts, alts_binds) ->
- returnSUs (StgPrimAlts discrim_ty stg_alts stg_deflt,
- deflt_binds `unionBags` unionManyBags alts_binds)
- where
- unboxed_alt_to_stg (lit, rhs)
- = coreExprToStg env rhs `thenSUs` \ (stg_rhs, rhs_binds) ->
- returnSUs ((lit, stg_rhs), rhs_binds)
-
-#ifdef DPH
- alts_to_stg (CoParAlgAlts tycon ctxt params alts deflt)
- = default_to_stg deflt `thenSUs` \ stg_deflt ->
- mapSUs boxed_alt_to_stg alts `thenSUs` \ stg_alts ->
- returnSUs (StgParAlgAlts discrim_ty ctxt params stg_alts stg_deflt)
- where
- boxed_alt_to_stg (con, rhs)
- = coreExprToStg env rhs `thenSUs` \ stg_rhs ->
- returnSUs (con, stg_rhs)
-
- alts_to_stg (CoParPrimAlts tycon ctxt alts deflt)
- = default_to_stg deflt `thenSUs` \ stg_deflt ->
- mapSUs unboxed_alt_to_stg alts `thenSUs` \ stg_alts ->
- returnSUs (StgParPrimAlts discrim_ty ctxt stg_alts stg_deflt)
+ = coreExprToStg env rhs `thenUs` \ stg_rhs ->
+ returnUs (con, bs, [ True | b <- bs ]{-bogus use mask-}, stg_rhs)
+
+ alts_to_stg discrim (PrimAlts alts deflt)
+ = default_to_stg discrim deflt `thenUs` \ stg_deflt ->
+ mapUs unboxed_alt_to_stg alts `thenUs` \ stg_alts ->
+ returnUs (StgPrimAlts discrim_ty stg_alts stg_deflt)
where
unboxed_alt_to_stg (lit, rhs)
- = coreExprToStg env rhs `thenSUs` \ stg_rhs ->
- returnSUs (lit, stg_rhs)
-#endif {- Data Parallel Haskell -}
+ = coreExprToStg env rhs `thenUs` \ stg_rhs ->
+ returnUs (lit, stg_rhs)
- default_to_stg discrim CoNoDefault
- = returnSUs (StgNoDefault, emptyBag)
+ default_to_stg discrim NoDefault
+ = returnUs StgNoDefault
- default_to_stg discrim (CoBindDefault binder rhs)
- = coreExprToStg new_env rhs `thenSUs` \ (stg_rhs, rhs_binds) ->
- returnSUs (StgBindDefault binder True{-used? no it is lying-} stg_rhs,
- rhs_binds)
- where
- --
- -- We convert case x of {...; x' -> ...x'...}
- -- to
- -- case x of {...; _ -> ...x... }
- --
- -- See notes in SimplCase.lhs, near simplDefault for the reasoning.
- -- It's quite easily done: simply extend the environment to bind the
- -- default binder to the scrutinee.
- --
- new_env = case discrim of
- CoVar v -> addOneToIdEnv env binder (stgLookup env v)
- other -> env
+ default_to_stg discrim (BindDefault binder rhs)
+ = coreExprToStg env rhs `thenUs` \ stg_rhs ->
+ returnUs (StgBindDefault binder True{-used? no it is lying-} stg_rhs)
\end{code}
%************************************************************************
%************************************************************************
\begin{code}
-coreExprToStg env (CoLet bind body)
- = coreBindToStg env bind `thenSUs` \ (stg_binds, new_env, float_binds1) ->
- coreExprToStg new_env body `thenSUs` \ (stg_body, float_binds2) ->
- returnSUs (mkStgLets stg_binds stg_body, float_binds1 `unionBags` float_binds2)
+coreExprToStg env (Let bind body)
+ = coreBindToStg env bind `thenUs` \ (stg_binds, new_env) ->
+ coreExprToStg new_env body `thenUs` \ stg_body ->
+ returnUs (mkStgLets stg_binds stg_body)
\end{code}
Covert core @scc@ expression directly to STG @scc@ expression.
\begin{code}
-coreExprToStg env (CoSCC cc expr)
- = coreExprToStg env expr `thenSUs` \ (stg_expr, binds) ->
- returnSUs (StgSCC (typeOfCoreExpr expr) cc stg_expr, binds)
+coreExprToStg env (Note (SCC cc) expr)
+ = coreExprToStg env expr `thenUs` \ stg_expr ->
+ returnUs (StgSCC (coreExprType expr) cc stg_expr)
\end{code}
-%************************************************************************
-%* *
-\subsubsection[coreToStg-dataParallel]{Data Parallel expressions}
-%* *
-%************************************************************************
\begin{code}
-#ifdef DPH
-coreExprToStg env (_, AnnCoParCon con ctxt types args)
- = mapAndUnzipSUs (arg2stg env) args `thenSUs` \ (stg_atoms, stg_binds) ->
- returnSUs (mkStgLets (catMaybes stg_binds)
- (StgParConApp con ctxt stg_atoms bOGUS_LVs))
-
-coreExprToStg env (_,AnnCoParComm ctxt expr comm)
- = coreExprToStg env expr `thenSUs` \ stg_expr ->
- annComm_to_stg comm `thenSUs` \ (stg_comm,stg_binds) ->
- returnSUs (mkStgLets (catMaybes stg_binds)
- (StgParComm ctxt stg_expr stg_comm))
- ))
- where
- annComm_to_stg (AnnCoParSend args)
- = mapAndUnzipSUs (arg2stg env) args `thenSUs` \ (stg_atoms, stg_binds) ->
- returnSUs (StgParSend stg_atoms,stg_binds)
-
- annComm_to_stg (AnnCoParFetch args)
- = mapAndUnzipSUs (arg2stg env) args `thenSUs` \ (stg_atoms, stg_binds) ->
- returnSUs (StgParFetch stg_atoms,stg_binds)
-
- annComm_to_stg (AnnCoToPodized)
- = returnSUs (StgToPodized,[])
- annComm_to_stg (AnnCoFromPodized)
- = returnSUs (StgFromPodized,[])
-#endif {- Data Parallel Haskell -}
+coreExprToStg env (Note other_note expr) = coreExprToStg env expr
\end{code}
-\begin{code}
-#ifdef DEBUG
-coreExprToStg env other = panic "coreExprToStg: it really failed here"
-#endif
-\end{code}
%************************************************************************
%* *
%* *
%************************************************************************
-Utilities.
+There's not anything interesting we can ASSERT about \tr{var} if it
+isn't in the StgEnv. (WDP 94/06)
+
+\begin{code}
+stgLookup :: StgEnv -> Id -> StgArg
+stgLookup env var = case (lookupIdEnv env var) of
+ Nothing -> StgVarArg var
+ Just atom -> atom
+\end{code}
Invent a fresh @Id@:
\begin{code}
-newStgVar :: UniType -> SUniqSM Id
+newStgVar :: Type -> UniqSM Id
newStgVar ty
- = getSUnique `thenSUs` \ uniq ->
- returnSUs (mkSysLocal SLIT("stg") uniq ty mkUnknownSrcLoc)
+ = getUnique `thenUs` \ uniq ->
+ returnUs (mkSysLocal SLIT("stg") uniq ty noSrcLoc)
+\end{code}
+
+\begin{code}
+newUniqueLocalId :: Id -> UniqSM Id
+newUniqueLocalId i =
+ getUnique `thenUs` \ uniq ->
+ returnUs (mkIdWithNewUniq i uniq)
+
+newLocalIds :: StgEnv -> Bool -> [Id] -> UniqSM ([Id], StgEnv)
+newLocalIds env maybe_visible [] = returnUs ([], env)
+newLocalIds env maybe_visible (i:is)
+ | maybe_visible && externallyVisibleId i =
+ newLocalIds env maybe_visible is `thenUs` \ (is', env') ->
+ returnUs (i:is', env')
+ | otherwise =
+ newUniqueLocalId i `thenUs` \ i' ->
+ let
+ new_env = addOneToIdEnv env i (StgVarArg i')
+ in
+ newLocalIds new_env maybe_visible is `thenUs` \ (is', env') ->
+ returnUs (i':is', env')
\end{code}
+
\begin{code}
-mkStgLets :: [PlainStgBinding]
- -> PlainStgExpr -- body of let
- -> PlainStgExpr
+mkStgLets :: [StgBinding]
+ -> StgExpr -- body of let
+ -> StgExpr
mkStgLets binds body = foldr StgLet body binds
+
+-- mk_app spots an StgCon in a function position,
+-- and turns it into an StgCon. See notes with
+-- getArgAmode in CgBindery.
+mk_app (StgConArg con) args = StgCon con args bOGUS_LVs
+mk_app other_fun args = StgApp other_fun args bOGUS_LVs
\end{code}
projects / ghc-hetmet.git / blobdiff