%
% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
-% $Id: CgMonad.lhs,v 1.20 1999/05/18 15:03:49 simonpj Exp $
+% $Id: CgMonad.lhs,v 1.27 2001/08/29 14:20:14 rje Exp $
%
\section[CgMonad]{The code generation monad}
forkEvalHelp, forkAbsC,
SemiTaggingStuff,
- addBindC, addBindsC, modifyBindC, lookupBindC,
-
EndOfBlockInfo(..),
setEndOfBlockInfo, getEndOfBlockInfo,
setSRTLabel, getSRTLabel,
+ setTickyCtrLabel, getTickyCtrLabel,
- StackUsage, HeapUsage,
+ StackUsage, Slot(..), HeapUsage,
- profCtrC, cgPanic,
+ profCtrC, profCtrAbsC,
costCentresC, moduleName,
Sequel(..), -- ToDo: unabstract?
sequelToAmode,
+ -- ideally we wouldn't export these, but some other modules access internal state
+ getState, setState, getInfoDown,
+
+ -- more localised access to monad state
+ getUsage, setUsage,
+ getBinds, setBinds, getStaticBinds,
+
-- out of general friendliness, we also export ...
CgInfoDownwards(..), CgState(..), -- non-abstract
CompilationInfo(..)
#include "HsVersions.h"
-import {-# SOURCE #-} CgBindery ( CgIdInfo(..), CgBindings, maybeStkLoc, nukeVolatileBinds )
+import {-# SOURCE #-} CgBindery ( CgBindings, nukeVolatileBinds )
import {-# SOURCE #-} CgUsages ( getSpRelOffset )
import AbsCSyn
import AbsCUtils ( mkAbsCStmts )
import CmdLineOpts ( opt_SccProfilingOn, opt_DoTickyProfiling )
-import CLabel ( CLabel, mkUpdInfoLabel, pprCLabel )
+import CLabel ( CLabel, mkUpdInfoLabel, mkTopTickyCtrLabel )
import Module ( Module )
import DataCon ( ConTag )
import Id ( Id )
import VarEnv
import PrimRep ( PrimRep(..) )
-import StgSyn ( StgLiveVars )
import Outputable
infixr 9 `thenC` -- Right-associative!
CLabel -- label of the current SRT
+ CLabel -- current destination for ticky counts
+
EndOfBlockInfo -- Info for stuff to do at end of basic block:
sequelToAmode UpdateCode = returnFC (CLbl mkUpdInfoLabel RetRep)
sequelToAmode (CaseAlts amode _) = returnFC amode
-sequelToAmode (SeqFrame _ _) = cgPanic (text "sequelToAmode: SeqFrame")
+sequelToAmode (SeqFrame _ _) = panic "sequelToAmode: SeqFrame"
type CgStksAndHeapUsage -- stacks and heap usage information
= (StackUsage, HeapUsage)
+data Slot = Free | NonPointer
+ deriving
+#ifdef DEBUG
+ (Eq,Show)
+#else
+ Eq
+#endif
+
type StackUsage =
(Int, -- virtSp: Virtual offset of topmost allocated slot
- [Int], -- free: List of free slots, in increasing order
+ [(Int,Slot)], -- free: List of free slots, in increasing order
Int, -- realSp: Virtual offset of real stack pointer
Int) -- hwSp: Highest value ever taken by virtSp
initialStateC = MkCgState AbsCNop emptyVarEnv initUsage
initUsage :: CgStksAndHeapUsage
-initUsage = ((0,[],0,0), (initVirtHp, initRealHp))
-initVirtHp = panic "Uninitialised virtual Hp"
-initRealHp = panic "Uninitialised real Hp"
+initUsage = ((0,[],0,0), (0,0))
\end{code}
"envInitForAlternatives" initialises the environment for a case alternative,
%************************************************************************
\begin{code}
-type FCode a = CgInfoDownwards -> CgState -> (a, CgState)
-type Code = CgInfoDownwards -> CgState -> CgState
+newtype FCode a = FCode (CgInfoDownwards -> CgState -> (a, CgState))
+type Code = FCode ()
+
+instance Monad FCode where
+ (>>=) = thenFC
+ return = returnFC
{-# INLINE thenC #-}
{-# INLINE thenFC #-}
\begin{code}
initC :: CompilationInfo -> Code -> AbstractC
-initC cg_info code
+initC cg_info (FCode code)
= case (code (MkCgInfoDown
cg_info
(error "initC: statics")
(error "initC: srt")
+ (mkTopTickyCtrLabel)
initEobInfo)
initialStateC) of
- MkCgState abc _ _ -> abc
+ ((),MkCgState abc _ _) -> abc
returnFC :: a -> FCode a
-
-returnFC val info_down state = (val, state)
+returnFC val = FCode (\info_down state -> (val, state))
\end{code}
\begin{code}
-thenC :: Code
- -> (CgInfoDownwards -> CgState -> a)
- -> CgInfoDownwards -> CgState -> a
-
--- thenC has both of the following types:
--- thenC :: Code -> Code -> Code
--- thenC :: Code -> FCode a -> FCode a
-
-thenC m k info_down state
- = k info_down new_state
- where
- new_state = m info_down state
+thenC :: Code -> FCode a -> FCode a
+thenC (FCode m) (FCode k) =
+ FCode (\info_down state -> let ((),new_state) = m info_down state in
+ k info_down new_state)
listCs :: [Code] -> Code
-
-listCs [] info_down state = state
-listCs (c:cs) info_down state = stateN
- where
- state1 = c info_down state
- stateN = listCs cs info_down state1
-
+listCs [] = return ()
+listCs (fc:fcs) = do
+ fc
+ listCs fcs
+
mapCs :: (a -> Code) -> [a] -> Code
-
-mapCs f [] info_down state = state
-mapCs f (c:cs) info_down state = stateN
- where
- state1 = (f c) info_down state
- stateN = mapCs f cs info_down state1
+mapCs = mapM_
\end{code}
\begin{code}
-thenFC :: FCode a
- -> (a -> CgInfoDownwards -> CgState -> c)
- -> CgInfoDownwards -> CgState -> c
-
--- thenFC :: FCode a -> (a -> FCode b) -> FCode b
--- thenFC :: FCode a -> (a -> Code) -> Code
-
-thenFC m k info_down state
- = k m_result info_down new_state
- where
- (m_result, new_state) = m info_down state
+thenFC :: FCode a -> (a -> FCode c) -> FCode c
+thenFC (FCode m) k = FCode (
+ \info_down state ->
+ let
+ (m_result, new_state) = m info_down state
+ (FCode kcode) = k m_result
+ in
+ kcode info_down new_state
+ )
listFCs :: [FCode a] -> FCode [a]
-
-listFCs [] info_down state = ([], state)
-listFCs (fc:fcs) info_down state = (thing : things, stateN)
- where
- (thing, state1) = fc info_down state
- (things, stateN) = listFCs fcs info_down state1
+listFCs = sequence
mapFCs :: (a -> FCode b) -> [a] -> FCode [b]
-
-mapFCs f [] info_down state = ([], state)
-mapFCs f (fc:fcs) info_down state = (thing : things, stateN)
- where
- (thing, state1) = (f fc) info_down state
- (things, stateN) = mapFCs f fcs info_down state1
+mapFCs = mapM
\end{code}
And the knot-tying combinator:
\begin{code}
fixC :: (a -> FCode a) -> FCode a
-fixC fcode info_down state = result
- where
- result@(v, _) = fcode v info_down state
- -- ^-------------^
+fixC fcode = FCode (
+ \info_down state ->
+ let
+ FCode fc = fcode v
+ result@(v,_) = fc info_down state
+ -- ^--------^
+ in
+ result
+ )
\end{code}
+Operators for getting and setting the state and "info_down".
+To maximise encapsulation, code should try to only get and set the
+state it actually uses.
+
+\begin{code}
+getState :: FCode CgState
+getState = FCode $ \info_down state -> (state,state)
+
+setState :: CgState -> FCode ()
+setState state = FCode $ \info_down _ -> ((),state)
+
+getUsage :: FCode CgStksAndHeapUsage
+getUsage = do
+ MkCgState absC binds usage <- getState
+ return usage
+
+setUsage :: CgStksAndHeapUsage -> FCode ()
+setUsage newusage = do
+ MkCgState absC binds usage <- getState
+ setState $ MkCgState absC binds newusage
+
+getBinds :: FCode CgBindings
+getBinds = do
+ MkCgState absC binds usage <- getState
+ return binds
+
+setBinds :: CgBindings -> FCode ()
+setBinds newbinds = do
+ MkCgState absC binds usage <- getState
+ setState $ MkCgState absC newbinds usage
+
+getStaticBinds :: FCode CgBindings
+getStaticBinds = do
+ (MkCgInfoDown _ static_binds _ _ _) <- getInfoDown
+ return static_binds
+
+withState :: FCode a -> CgState -> FCode (a,CgState)
+withState (FCode fcode) newstate = FCode $ \info_down state ->
+ let (retval, state2) = fcode info_down newstate in ((retval,state2), state)
+
+getInfoDown :: FCode CgInfoDownwards
+getInfoDown = FCode $ \info_down state -> (info_down,state)
+
+withInfoDown :: FCode a -> CgInfoDownwards -> FCode a
+withInfoDown (FCode fcode) info_down = FCode $ \_ state -> fcode info_down state
+
+doFCode :: FCode a -> CgInfoDownwards -> CgState -> (a,CgState)
+doFCode (FCode fcode) info_down state = fcode info_down state
+\end{code}
+
+
@forkClosureBody@ takes a code, $c$, and compiles it in a completely
fresh environment, except that:
- compilation info and statics are passed in unchanged.
\begin{code}
forkClosureBody :: Code -> Code
-forkClosureBody code
- (MkCgInfoDown cg_info statics srt _)
- (MkCgState absC_in binds un_usage)
- = MkCgState (AbsCStmts absC_in absC_fork) binds un_usage
- where
- fork_state = code body_info_down initialStateC
- MkCgState absC_fork _ _ = fork_state
- body_info_down = MkCgInfoDown cg_info statics srt initEobInfo
-
+forkClosureBody (FCode code) = do
+ (MkCgInfoDown cg_info statics srt ticky _) <- getInfoDown
+ (MkCgState absC_in binds un_usage) <- getState
+ let body_info_down = MkCgInfoDown cg_info statics srt ticky initEobInfo
+ let ((),fork_state) = code body_info_down initialStateC
+ let MkCgState absC_fork _ _ = fork_state
+ setState $ MkCgState (AbsCStmts absC_in absC_fork) binds un_usage
+
forkStatics :: FCode a -> FCode a
-forkStatics fcode (MkCgInfoDown cg_info _ srt _)
- (MkCgState absC_in statics un_usage)
- = (result, MkCgState (AbsCStmts absC_in absC_fork) statics un_usage)
- where
- (result, state) = fcode rhs_info_down initialStateC
- MkCgState absC_fork _ _ = state -- Don't merge these this line with the one
- -- above or it becomes too strict!
- rhs_info_down = MkCgInfoDown cg_info statics srt initEobInfo
+forkStatics (FCode fcode) = FCode (
+ \(MkCgInfoDown cg_info _ srt ticky _)
+ (MkCgState absC_in statics un_usage)
+ ->
+ let
+ (result, state) = fcode rhs_info_down initialStateC
+ MkCgState absC_fork _ _ = state -- Don't merge these this line with the one
+ -- above or it becomes too strict!
+ rhs_info_down = MkCgInfoDown cg_info statics srt ticky initEobInfo
+ in
+ (result, MkCgState (AbsCStmts absC_in absC_fork) statics un_usage)
+ )
forkAbsC :: Code -> FCode AbstractC
-forkAbsC code info_down (MkCgState absC1 bs usage)
- = (absC2, new_state)
- where
- MkCgState absC2 _ ((_, _, _,h2), _) =
- code info_down (MkCgState AbsCNop bs usage)
- ((v, f, r, h1), heap_usage) = usage
-
- new_usage = ((v, f, r, h1 `max` h2), heap_usage)
- new_state = MkCgState absC1 bs new_usage
+forkAbsC (FCode code) =
+ do
+ info_down <- getInfoDown
+ (MkCgState absC1 bs usage) <- getState
+ let ((),MkCgState absC2 _ ((_, _, _,h2), _)) = code info_down (MkCgState AbsCNop bs usage)
+ let ((v, f, r, h1), heap_usage) = usage
+ let new_usage = ((v, f, r, h1 `max` h2), heap_usage)
+ setState $ MkCgState absC1 bs new_usage
+ return absC2
\end{code}
@forkAlts@ $bs~d$ takes fcodes $bs$ for the branches of a @case@, and
\begin{code}
forkAlts :: [FCode a] -> FCode b -> FCode ([a],b)
-forkAlts branch_fcodes deflt_fcode info_down in_state
- = ((branch_results , deflt_result), out_state)
- where
- compile fc = fc info_down in_state
-
- (branch_results, branch_out_states) = unzip (map compile branch_fcodes)
-
- (deflt_result, deflt_out_state) = deflt_fcode info_down in_state
+forkAlts branch_fcodes (FCode deflt_fcode) =
+ do
+ info_down <- getInfoDown
+ in_state <- getState
+ let compile (FCode fc) = fc info_down in_state
+ let (branch_results, branch_out_states) = unzip (map compile branch_fcodes)
+ let (deflt_result, deflt_out_state) = deflt_fcode info_down in_state
+ setState $ foldl stateIncUsage in_state (deflt_out_state:branch_out_states)
+ -- NB foldl. in_state is the *left* argument to stateIncUsage
+ return (branch_results, deflt_result)
- out_state = foldl stateIncUsage in_state (deflt_out_state:branch_out_states)
- -- NB foldl. in_state is the *left* argument to stateIncUsage
\end{code}
@forkEval@ takes two blocks of code.
-> FCode (Int, -- Sp
a) -- Result of the FCode
-forkEvalHelp body_eob_info env_code body_code
- info_down@(MkCgInfoDown cg_info statics srt _) state
- = ((v,value_returned), state `stateIncUsageEval` state_at_end_return)
- where
- info_down_for_body = MkCgInfoDown cg_info statics srt body_eob_info
-
- (MkCgState _ binds ((v,f,_,_), _)) = env_code info_down_for_body state
- -- These v and f things are now set up as the body code expects them
-
- (value_returned, state_at_end_return)
- = body_code info_down_for_body state_for_body
-
- state_for_body = MkCgState AbsCNop
+forkEvalHelp body_eob_info env_code body_code =
+ do
+ info_down@(MkCgInfoDown cg_info statics srt ticky _) <- getInfoDown
+ state <- getState
+ let info_down_for_body = MkCgInfoDown cg_info statics srt ticky body_eob_info
+ let (_,MkCgState _ binds ((v,f,_,_),_)) =
+ doFCode env_code info_down_for_body state
+ let state_for_body = MkCgState AbsCNop
(nukeVolatileBinds binds)
- ((v,f,v,v),
- (initVirtHp, initRealHp))
-
-
+ ((v,f,v,v), (0,0))
+ let (value_returned, state_at_end_return) =
+ doFCode body_code info_down_for_body state_for_body
+ setState $ state `stateIncUsageEval` state_at_end_return
+ return (v,value_returned)
+
stateIncUsageEval :: CgState -> CgState -> CgState
stateIncUsageEval (MkCgState absC1 bs ((v,f,r,h1),heap_usage))
(MkCgState absC2 _ ((_,_,_,h2), _))
- = MkCgState (absC1 `AbsCStmts` absC2)
+ = MkCgState (absC1 `mkAbsCStmts` absC2)
-- The AbsC coming back should consist only of nested declarations,
-- notably of the return vector!
bs
environment; @absC@ glues @ab_C@ onto the Abstract~C collected so far.
\begin{code}
nopC :: Code
-nopC info_down state = state
+nopC = return ()
absC :: AbstractC -> Code
-absC more_absC info_down state@(MkCgState absC binds usage)
- = MkCgState (mkAbsCStmts absC more_absC) binds usage
+absC more_absC = do
+ state@(MkCgState absC binds usage) <- getState
+ setState $ MkCgState (mkAbsCStmts absC more_absC) binds usage
\end{code}
These two are just like @absC@, except they examine the compilation
\begin{code}
costCentresC :: FAST_STRING -> [CAddrMode] -> Code
-costCentresC macro args _ state@(MkCgState absC binds usage)
- = if opt_SccProfilingOn
- then MkCgState (mkAbsCStmts absC (CCallProfCCMacro macro args)) binds usage
- else state
+costCentresC macro args =
+ if opt_SccProfilingOn then do
+ (MkCgState absC binds usage) <- getState
+ setState $ MkCgState (mkAbsCStmts absC (CCallProfCCMacro macro args)) binds usage
+ else
+ nopC
profCtrC :: FAST_STRING -> [CAddrMode] -> Code
-profCtrC macro args _ state@(MkCgState absC binds usage)
+profCtrC macro args =
+ if not opt_DoTickyProfiling
+ then nopC
+ else do
+ (MkCgState absC binds usage) <- getState
+ setState $ MkCgState (mkAbsCStmts absC (CCallProfCtrMacro macro args)) binds usage
+
+profCtrAbsC :: FAST_STRING -> [CAddrMode] -> AbstractC
+
+profCtrAbsC macro args
= if not opt_DoTickyProfiling
- then state
- else MkCgState (mkAbsCStmts absC (CCallProfCtrMacro macro args)) binds usage
+ then AbsCNop
+ else CCallProfCtrMacro macro args
{- Try to avoid adding too many special compilation strategies here.
It's better to modify the header files as necessary for particular
\begin{code}
getAbsC :: Code -> FCode AbstractC
-
-getAbsC code info_down (MkCgState absC binds usage)
- = (absC2, MkCgState absC binds2 usage2)
- where
- (MkCgState absC2 binds2 usage2)
- = code info_down (MkCgState AbsCNop binds usage)
+getAbsC code = do
+ MkCgState absC binds usage <- getState
+ ((),MkCgState absC2 binds2 usage2) <- withState code (MkCgState AbsCNop binds usage)
+ setState $ MkCgState absC binds2 usage2
+ return absC2
\end{code}
\begin{code}
-
moduleName :: FCode Module
-moduleName (MkCgInfoDown (MkCompInfo mod_name) _ _ _) state
- = (mod_name, state)
-
+moduleName = do
+ (MkCgInfoDown (MkCompInfo mod_name) _ _ _ _) <- getInfoDown
+ return mod_name
\end{code}
\begin{code}
setEndOfBlockInfo :: EndOfBlockInfo -> Code -> Code
-setEndOfBlockInfo eob_info code (MkCgInfoDown c_info statics srt _) state
- = code (MkCgInfoDown c_info statics srt eob_info) state
+setEndOfBlockInfo eob_info code = do
+ (MkCgInfoDown c_info statics srt ticky _) <- getInfoDown
+ withInfoDown code (MkCgInfoDown c_info statics srt ticky eob_info)
getEndOfBlockInfo :: FCode EndOfBlockInfo
-getEndOfBlockInfo (MkCgInfoDown c_info statics _ eob_info) state
- = (eob_info, state)
+getEndOfBlockInfo = do
+ (MkCgInfoDown c_info statics _ _ eob_info) <- getInfoDown
+ return eob_info
\end{code}
\begin{code}
getSRTLabel :: FCode CLabel
-getSRTLabel (MkCgInfoDown _ _ srt _) state
- = (srt, state)
+getSRTLabel = do
+ (MkCgInfoDown _ _ srt _ _) <- getInfoDown
+ return srt
setSRTLabel :: CLabel -> Code -> Code
-setSRTLabel srt code (MkCgInfoDown c_info statics _ eob_info) state
- = code (MkCgInfoDown c_info statics srt eob_info) state
+setSRTLabel srt code = do
+ (MkCgInfoDown c_info statics _ ticky eob_info) <- getInfoDown
+ withInfoDown code (MkCgInfoDown c_info statics srt ticky eob_info)
\end{code}
-%************************************************************************
-%* *
-\subsection[CgMonad-bindery]{Monad things for fiddling with @CgBindings@}
-%* *
-%************************************************************************
-
-There are three basic routines, for adding (@addBindC@), modifying
-(@modifyBindC@) and looking up (@lookupBindC@) bindings.
-
-A @Id@ is bound to a @(VolatileLoc, StableLoc)@ triple.
-The name should not already be bound. (nice ASSERT, eh?)
-
\begin{code}
-addBindC :: Id -> CgIdInfo -> Code
-addBindC name stuff_to_bind info_down (MkCgState absC binds usage)
- = MkCgState absC (extendVarEnv binds name stuff_to_bind) usage
-
-addBindsC :: [(Id, CgIdInfo)] -> Code
-addBindsC new_bindings info_down (MkCgState absC binds usage)
- = MkCgState absC new_binds usage
- where
- new_binds = foldl (\ binds (name,info) -> extendVarEnv binds name info)
- binds
- new_bindings
-
-modifyBindC :: Id -> (CgIdInfo -> CgIdInfo) -> Code
-modifyBindC name mangle_fn info_down (MkCgState absC binds usage)
- = MkCgState absC (modifyVarEnv mangle_fn binds name) usage
-
-lookupBindC :: Id -> FCode CgIdInfo
-lookupBindC name info_down@(MkCgInfoDown _ static_binds srt _)
- state@(MkCgState absC local_binds usage)
- = (val, state)
- where
- val = case (lookupVarEnv local_binds name) of
- Nothing -> try_static
- Just this -> this
-
- try_static =
- case (lookupVarEnv static_binds name) of
- Just this -> this
- Nothing
- -> cgPanic (text "lookupBindC: no info for" <+> ppr name) info_down state
-
-cgPanic :: SDoc -> CgInfoDownwards -> CgState -> a
-cgPanic doc info_down@(MkCgInfoDown _ static_binds srt _)
- state@(MkCgState absC local_binds usage)
- = pprPanic "cgPanic"
- (vcat [doc,
- ptext SLIT("static binds for:"),
- vcat [ ppr i | (MkCgIdInfo i _ _ _) <- rngVarEnv static_binds ],
- ptext SLIT("local binds for:"),
- vcat [ ppr i | (MkCgIdInfo i _ _ _) <- rngVarEnv local_binds ],
- ptext SLIT("SRT label") <+> pprCLabel srt
- ])
+getTickyCtrLabel :: FCode CLabel
+getTickyCtrLabel = do
+ (MkCgInfoDown _ _ _ ticky _) <- getInfoDown
+ return ticky
+
+setTickyCtrLabel :: CLabel -> Code -> Code
+setTickyCtrLabel ticky code = do
+ (MkCgInfoDown c_info statics srt _ eob_info) <- getInfoDown
+ withInfoDown code (MkCgInfoDown c_info statics srt ticky eob_info)
\end{code}