b1416bb0cf
This touches an awful lot of code, but cgtest07/17 (arrays and retyping) pass. This is useful because there are going to be places in the future where we'll want to represent dimensions that are known at runtime but not at compile time -- for example, mobile allocations, or dynamically-sized arrays. It simplifies the code in a number of places. However, we do now need to be careful that expressions containing variables do not leak into the State, since they won't be affected by later passes. Two caveats (marked as FIXMEs in the source): - Retypes checking in the occam parser is disabled, since the plan is to move it out to a pass anyway. - There's some (now very obvious) duplication, particularly in the backend, of bits of code that construct expressions for the total size of an array (either in bytes or elements); this should be moved to a couple of helper functions that everything can use.
326 lines
16 KiB
Haskell
326 lines
16 KiB
Haskell
{-
|
|
Tock: a compiler for parallel languages
|
|
Copyright (C) 2007 University of Kent
|
|
|
|
This program is free software; you can redistribute it and/or modify it
|
|
under the terms of the GNU General Public License as published by the
|
|
Free Software Foundation, either version 2 of the License, or (at your
|
|
option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful, but
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License along
|
|
with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
-}
|
|
|
|
-- | Passes associated with the backends
|
|
module BackendPasses where
|
|
|
|
import Control.Monad.State
|
|
import Data.Generics
|
|
import qualified Data.Map as Map
|
|
|
|
import qualified AST as A
|
|
import CompState
|
|
import Errors
|
|
import Metadata
|
|
import Pass
|
|
import PrettyShow
|
|
import qualified Properties as Prop
|
|
import Types
|
|
import Utils
|
|
|
|
squashArrays :: [Pass]
|
|
squashArrays = makePassesDep
|
|
[ ("Declare array-size arrays", declareSizesArray, prereq ++ [Prop.slicesSimplified], [Prop.arraySizesDeclared])
|
|
, ("Add array-size arrays to PROC headers", addSizesFormalParameters, prereq ++ [Prop.arraySizesDeclared], [])
|
|
, ("Add array-size arrays to PROC calls", addSizesActualParameters, prereq ++ [Prop.arraySizesDeclared], [])
|
|
, ("Simplify array slices", simplifySlices, prereq, [Prop.slicesSimplified])
|
|
]
|
|
where
|
|
prereq = Prop.agg_namesDone ++ Prop.agg_typesDone ++ Prop.agg_functionsGone ++ [Prop.subscriptsPulledUp, Prop.arrayLiteralsExpanded]
|
|
|
|
transformWaitFor :: Data t => t -> PassM t
|
|
transformWaitFor = doGeneric `extM` doAlt
|
|
where
|
|
doGeneric :: Data t => t -> PassM t
|
|
doGeneric = makeGeneric transformWaitFor
|
|
|
|
doAlt :: A.Process -> PassM A.Process
|
|
doAlt a@(A.Alt m pri s)
|
|
= do (s',(specs,code)) <- runStateT (applyToOnly doWaitFor s) ([],[])
|
|
if (null specs && null code)
|
|
then return a
|
|
else return $ A.Seq m $ foldr addSpec (A.Several m (code ++ [A.Only m $ A.Alt m pri s'])) specs
|
|
doAlt p = doGeneric p
|
|
|
|
addSpec :: Data a => (A.Structured a -> A.Structured a) -> A.Structured a -> A.Structured a
|
|
addSpec spec inner = spec inner
|
|
|
|
doWaitFor :: A.Alternative -> StateT ([A.Structured A.Process -> A.Structured A.Process], [A.Structured A.Process]) PassM A.Alternative
|
|
doWaitFor a@(A.AlternativeWait m A.WaitFor e p)
|
|
= do (specs, init) <- get
|
|
id <- lift $ makeNonce "waitFor"
|
|
let n = (A.Name m A.VariableName id)
|
|
let var = A.Variable m n
|
|
put (specs ++ [A.Spec m (A.Specification m n (A.Declaration m A.Time))],
|
|
init ++ [A.Only m $ A.GetTime m var, A.Only m $ A.Assign m [var] $ A.ExpressionList m [A.Dyadic m A.Plus (A.ExprVariable m var) e]])
|
|
return $ A.AlternativeWait m A.WaitUntil (A.ExprVariable m var) p
|
|
|
|
doWaitFor a = return a
|
|
|
|
append_sizes :: A.Name -> A.Name
|
|
append_sizes n = n {A.nameName = A.nameName n ++ "_sizes"}
|
|
|
|
|
|
-- | Declares a _sizes array for every array, statically sized or dynamically sized.
|
|
-- For each record type it declares a _sizes array too.
|
|
declareSizesArray :: Data t => t -> PassM t
|
|
declareSizesArray = doGeneric `ext1M` doStructured
|
|
where
|
|
defineSizesName :: Meta -> A.Name -> A.SpecType -> PassM ()
|
|
defineSizesName m n spec
|
|
= defineName n $ A.NameDef {
|
|
A.ndMeta = m
|
|
,A.ndName = A.nameName n
|
|
,A.ndOrigName = A.nameName n
|
|
,A.ndNameType = A.VariableName
|
|
,A.ndType = spec
|
|
,A.ndAbbrevMode = A.ValAbbrev
|
|
,A.ndPlacement = A.Unplaced}
|
|
|
|
-- Strips all the array subscripts from a variable:
|
|
findInnerVar :: A.Variable -> (Maybe A.Expression, A.Variable)
|
|
findInnerVar wv@(A.SubscriptedVariable m sub v) = case sub of
|
|
A.SubscriptField {} -> (Nothing, wv)
|
|
A.SubscriptFromFor _ _ for -> (Just for, snd $ findInnerVar v) -- Keep the outer most
|
|
A.Subscript {} -> findInnerVar v
|
|
findInnerVar v = (Nothing, v)
|
|
|
|
-- | Generate the @_sizes@ array for a 'Retypes' expression.
|
|
retypesSizes :: Meta -> A.Name -> [A.Dimension] -> A.Type -> A.Variable -> PassM A.Specification
|
|
retypesSizes m n_sizes ds elemT v@(A.Variable _ nSrc)
|
|
= do biDest <- bytesInType (A.Array ds elemT)
|
|
tSrc <- typeOfVariable v
|
|
biSrc <- bytesInType tSrc
|
|
|
|
-- Figure out the size of the source.
|
|
srcSize <-
|
|
case (biSrc, tSrc) of
|
|
-- Fixed-size source -- easy.
|
|
(BIJust size, _) -> return size
|
|
-- Variable-size source -- it must be an array, so multiply
|
|
-- together the dimensions.
|
|
(_, A.Array ds t) ->
|
|
do BIJust elementSize <- bytesInType t
|
|
return $ foldl mulExprs elementSize dSizes
|
|
where
|
|
srcSizes = A.Variable m $ append_sizes nSrc
|
|
dSizes = [case d of
|
|
-- Fixed dimension.
|
|
A.Dimension e -> e
|
|
-- Variable dimension -- use the corresponding
|
|
-- element of its _sizes array.
|
|
A.UnknownDimension ->
|
|
A.ExprVariable m $ A.SubscriptedVariable m (A.Subscript m A.NoCheck $ makeConstant m i) srcSizes
|
|
| (d, i) <- zip ds [0..]]
|
|
_ -> dieP m "Cannot compute size of source type"
|
|
|
|
-- Build the _sizes array for the destination.
|
|
sizeSpecType <-
|
|
case biDest of
|
|
-- Destination size is fixed -- so we must know the dimensions.
|
|
BIJust _ ->
|
|
return $ makeStaticSizeSpec m n_sizes ds
|
|
-- Destination has one free dimension, so we need to compute
|
|
-- it.
|
|
BIOneFree destSize n ->
|
|
let newDim = A.Dimension $ divExprs srcSize destSize
|
|
ds' = replaceAt n newDim ds in
|
|
return $ makeStaticSizeSpec m n_sizes ds'
|
|
|
|
defineSizesName m n_sizes sizeSpecType
|
|
return $ A.Specification m n_sizes sizeSpecType
|
|
|
|
abbrevVarSizes :: Meta -> A.Name -> [A.Dimension] -> A.Variable -> PassM A.Specification
|
|
abbrevVarSizes m n_sizes ds outerV
|
|
= do -- Find the inner most variable (i.e. strip all the array subscripts)
|
|
let (sliceSize, innerV) = findInnerVar outerV
|
|
-- Figure out the _sizes variable to abbreviate; either the _sizes variable corresponding
|
|
-- to the abbreviation source (for everything but record fields)
|
|
-- or the globally declared record field _sizes constant
|
|
varSrcSizes <- case innerV of
|
|
A.Variable _ srcN -> return (A.Variable m $ append_sizes srcN)
|
|
A.SubscriptedVariable _ (A.SubscriptField _ fieldName) recordV ->
|
|
do A.Record recordName <- typeOfVariable recordV
|
|
return (A.Variable m $ A.Name m A.VariableName $ A.nameName recordName ++ A.nameName fieldName ++ "_sizes")
|
|
-- Get the dimensions of the source variable:
|
|
(A.Array srcDs _) <- typeOfVariable innerV
|
|
-- Calculate the correct subscript into the source _sizes variable to get to the dimensions for the destination:
|
|
let sizeDiff = length srcDs - length ds
|
|
subSrcSizeVar = A.SubscriptedVariable m (A.SubscriptFromFor m (makeConstant m sizeDiff) (makeConstant m $ length ds)) varSrcSizes
|
|
sizeType = A.Array [makeDimension m $ length ds] A.Int
|
|
sizeSpecType = case sliceSize of
|
|
Just exp -> let subDims = [A.SubscriptedVariable m (A.Subscript m A.NoCheck $ makeConstant m n) varSrcSizes | n <- [1 .. (length srcDs - 1)]] in
|
|
A.IsExpr m A.ValAbbrev sizeType $
|
|
A.Literal m sizeType $ A.ArrayLiteral m $
|
|
[A.ArrayElemExpr exp] ++ map (A.ArrayElemExpr . A.ExprVariable m) subDims
|
|
Nothing -> A.Is m A.ValAbbrev sizeType subSrcSizeVar
|
|
defineSizesName m n_sizes sizeSpecType
|
|
return $ A.Specification m n_sizes sizeSpecType
|
|
|
|
|
|
doGeneric :: Data t => t -> PassM t
|
|
doGeneric = makeGeneric declareSizesArray
|
|
|
|
doStructured :: Data a => A.Structured a -> PassM (A.Structured a)
|
|
doStructured str@(A.Spec m sp@(A.Specification m' n spec) s)
|
|
= do t <- typeOfSpec spec
|
|
case (spec,t) of
|
|
(_,Just (A.Array ds elemT)) ->
|
|
do sizeSpec <- if elem A.UnknownDimension ds
|
|
then
|
|
-- At least one unknown dimension:
|
|
case spec of
|
|
-- TODO I think retyping a channel array ends up here, and probably isn't handled right
|
|
(A.Retypes _ _ _ v) -> retypesSizes m' (append_sizes n) ds elemT v
|
|
_ ->
|
|
let n_sizes = append_sizes n in
|
|
case spec of
|
|
A.Is _ _ _ v -> abbrevVarSizes m n_sizes ds v
|
|
A.IsExpr _ _ _ (A.ExprVariable _ v) -> abbrevVarSizes m n_sizes ds v
|
|
-- The dimensions in a literal should all be static:
|
|
A.IsExpr _ _ _ (A.Literal _ (A.Array ds _) _) ->
|
|
do let sizeSpecType = makeStaticSizeSpec m' n_sizes ds
|
|
defineSizesName m' n_sizes sizeSpecType
|
|
return $ A.Specification m' n_sizes sizeSpecType
|
|
_ -> dieP m $ "Could not handle unknown array spec: " ++ pshow spec
|
|
-- Everything is statically sized:
|
|
else do let n_sizes = append_sizes n
|
|
sizeSpecType = makeStaticSizeSpec m' n_sizes ds
|
|
sizeSpec = A.Specification m' n_sizes sizeSpecType
|
|
defineSizesName m' n_sizes sizeSpecType
|
|
return sizeSpec
|
|
s' <- doStructured s
|
|
return (A.Spec m sizeSpec $ A.Spec m sp $ s')
|
|
(A.RecordType m _ fs, _) ->
|
|
do s' <- doStructured s
|
|
fieldDeclarations <- foldM (declareFieldSizes (A.nameName n) m) s' fs
|
|
return $ A.Spec m sp fieldDeclarations
|
|
_ -> doGeneric str
|
|
doStructured s = doGeneric s
|
|
|
|
makeStaticSizeSpec :: Meta -> A.Name -> [A.Dimension] -> A.SpecType
|
|
makeStaticSizeSpec m n ds = makeDynamicSizeSpec m n es
|
|
where
|
|
es = [e | A.Dimension e <- ds]
|
|
|
|
makeDynamicSizeSpec :: Meta -> A.Name -> [A.Expression] -> A.SpecType
|
|
makeDynamicSizeSpec m n es = sizeSpecType
|
|
where
|
|
sizeType = A.Array [makeDimension m $ length es] A.Int
|
|
sizeLit = A.Literal m sizeType $ A.ArrayLiteral m $ map A.ArrayElemExpr es
|
|
sizeSpecType = A.IsExpr m A.ValAbbrev sizeType sizeLit
|
|
|
|
declareFieldSizes :: Data a => String -> Meta -> A.Structured a -> (A.Name, A.Type) -> PassM (A.Structured a)
|
|
declareFieldSizes prep m inner (n, A.Array ds _)
|
|
= do let n_sizes = n {A.nameName = prep ++ A.nameName n}
|
|
sizeSpecType = makeStaticSizeSpec m n_sizes ds
|
|
defineSizesName m n_sizes sizeSpecType
|
|
return $ A.Spec m (A.Specification m n_sizes sizeSpecType) inner
|
|
declareFieldSizes _ _ s _ = return s
|
|
|
|
-- | A pass for adding _sizes parameters to PROC arguments
|
|
-- TODO in future, only add _sizes for variable-sized parameters
|
|
addSizesFormalParameters :: Data t => t -> PassM t
|
|
addSizesFormalParameters = doGeneric `extM` doSpecification
|
|
where
|
|
doGeneric :: Data t => t -> PassM t
|
|
doGeneric = makeGeneric addSizesFormalParameters
|
|
|
|
doSpecification :: A.Specification -> PassM A.Specification
|
|
doSpecification (A.Specification m n (A.Proc m' sm args body))
|
|
= do (args', newargs) <- transformFormals m args
|
|
body' <- doGeneric body
|
|
let newspec = A.Proc m' sm args' body'
|
|
modify (\cs -> cs {csNames = Map.adjust (\nd -> nd { A.ndType = newspec }) (A.nameName n) (csNames cs)})
|
|
mapM_ (recordArg m') newargs
|
|
return $ A.Specification m n newspec
|
|
doSpecification st = doGeneric st
|
|
|
|
recordArg :: Meta -> A.Formal -> PassM ()
|
|
recordArg m (A.Formal am t n)
|
|
= defineName n $ A.NameDef {
|
|
A.ndMeta = m
|
|
,A.ndName = A.nameName n
|
|
,A.ndOrigName = A.nameName n
|
|
,A.ndNameType = A.VariableName
|
|
,A.ndType = A.Declaration m t
|
|
,A.ndAbbrevMode = A.ValAbbrev
|
|
,A.ndPlacement = A.Unplaced}
|
|
|
|
transformFormals :: Meta -> [A.Formal] -> PassM ([A.Formal], [A.Formal])
|
|
transformFormals _ [] = return ([],[])
|
|
transformFormals m ((f@(A.Formal am t n)):fs)
|
|
= case t of
|
|
A.Array ds _ -> do let sizeType = A.Array [makeDimension m $ length ds] A.Int
|
|
let newf = A.Formal A.ValAbbrev sizeType (append_sizes n)
|
|
(rest, moreNew) <- transformFormals m fs
|
|
return (f : newf : rest, newf : moreNew)
|
|
_ -> do (rest, new) <- transformFormals m fs
|
|
return (f : rest, new)
|
|
|
|
-- | A pass for adding _sizes parameters to actuals in PROC calls
|
|
addSizesActualParameters :: Data t => t -> PassM t
|
|
addSizesActualParameters = doGeneric `extM` doProcess
|
|
where
|
|
doGeneric :: Data t => t -> PassM t
|
|
doGeneric = makeGeneric addSizesActualParameters
|
|
|
|
doProcess :: A.Process -> PassM A.Process
|
|
doProcess (A.ProcCall m n params) = concatMapM transformActual params >>* A.ProcCall m n
|
|
doProcess p = doGeneric p
|
|
|
|
transformActual :: A.Actual -> PassM [A.Actual]
|
|
transformActual a@(A.ActualVariable am (A.Array ds _) (A.Variable m n))
|
|
= do let a_sizes = A.Variable m (append_sizes n)
|
|
let sizeType = A.Array [makeDimension m $ length ds] A.Int
|
|
return [a, A.ActualVariable A.ValAbbrev sizeType a_sizes]
|
|
transformActual a@(A.ActualExpression (A.Array ds _) (A.ExprVariable _ (A.Variable m n)))
|
|
= do let a_sizes = A.Variable m (append_sizes n)
|
|
let sizeType = A.Array [makeDimension m $ length ds] A.Int
|
|
return [a, A.ActualVariable A.ValAbbrev sizeType a_sizes]
|
|
transformActual a = let t = case a of
|
|
A.ActualVariable _ t _ -> t
|
|
A.ActualExpression t _ -> t
|
|
in case t of
|
|
A.Array {} -> dieP (findMeta a) "Untransformed actual parameter of type array: "
|
|
_ -> return [a]
|
|
|
|
-- | Transforms all slices into the FromFor form.
|
|
simplifySlices :: Data t => t -> PassM t
|
|
simplifySlices = doGeneric `extM` doVariable
|
|
where
|
|
doGeneric :: Data t => t -> PassM t
|
|
doGeneric = makeGeneric simplifySlices
|
|
|
|
-- We recurse into the subscripts in case they contain subscripts:
|
|
doVariable :: A.Variable -> PassM A.Variable
|
|
doVariable (A.SubscriptedVariable m (A.SubscriptFor m' for) v)
|
|
= do for' <- doGeneric for
|
|
v' <- doGeneric v
|
|
return (A.SubscriptedVariable m (A.SubscriptFromFor m' (makeConstant m' 0) for') v')
|
|
doVariable (A.SubscriptedVariable m (A.SubscriptFrom m' from) v)
|
|
= do v' <- doGeneric v
|
|
A.Array (d:_) _ <- typeOfVariable v'
|
|
limit <- case d of
|
|
A.Dimension n -> return n
|
|
A.UnknownDimension -> return $ A.SizeVariable m' v'
|
|
from' <- doGeneric from
|
|
return (A.SubscriptedVariable m (A.SubscriptFromFor m' from' (A.Dyadic m A.Subtr limit from')) v')
|
|
-- We must recurse, to handle nested variables, and variables inside subscripts!
|
|
doVariable v = doGeneric v
|