Safe Haskell	Safe
Language	Haskell2010

Body

type Body n = LabelMap (Block n C C) Source

A (possibly empty) collection of closed/closed blocks

type Body' block n = LabelMap (block n C C) Source

Body abstracted over block

emptyBody :: Body' block n Source

bodyList :: NonLocal (block n) => Body' block n -> [(Label, block n C C)] Source

addBlock :: NonLocal thing => thing C C -> LabelMap (thing C C) -> LabelMap (thing C C) Source

bodyUnion :: forall a. LabelMap a -> LabelMap a -> LabelMap a Source

Graph

type Graph = Graph' Block Source

A control-flow graph, which may take any of four shapes (O/O, OC, CO, C/C). A graph open at the entry has a single, distinguished, anonymous entry point; if a graph is closed at the entry, its entry point(s) are supplied by a context.

data Graph' block n e x where Source

Graph' is abstracted over the block type, so that we can build graphs of annotated blocks for example (Compiler.Hoopl.Dataflow needs this).

class NonLocal thing where Source

Gives access to the anchor points for nonlocal edges as well as the edges themselves

Constructing graphs

bodyGraph :: Body n -> Graph n C C Source

blockGraph :: NonLocal n => Block n e x -> Graph n e x Source

gUnitOO :: block n O O -> Graph' block n O O Source

gUnitOC :: block n O C -> Graph' block n O C Source

gUnitCO :: block n C O -> Graph' block n C O Source

gUnitCC :: NonLocal (block n) => block n C C -> Graph' block n C C Source

catGraphNodeOC :: NonLocal n => Graph n e O -> n O C -> Graph n e C Source

catGraphNodeOO :: Graph n e O -> n O O -> Graph n e O Source

catNodeCOGraph :: NonLocal n => n C O -> Graph n O x -> Graph n C x Source

catNodeOOGraph :: n O O -> Graph n O x -> Graph n O x Source

Splicing graphs

splice :: forall block n e a x. NonLocal (block n) => (forall e x. block n e O -> block n O x -> block n e x) -> Graph' block n e a -> Graph' block n a x -> Graph' block n e x Source

gSplice :: NonLocal n => Graph n e a -> Graph n a x -> Graph n e x Source

Maps

mapGraph :: (forall e x. n e x -> n' e x) -> Graph n e x -> Graph n' e x Source

Maps over all nodes in a graph.

mapGraphBlocks :: forall block n block' n' e x. (forall e x. block n e x -> block' n' e x) -> Graph' block n e x -> Graph' block' n' e x Source

Function mapGraphBlocks enables a change of representation of blocks, nodes, or both. It lifts a polymorphic block transform into a polymorphic graph transform. When the block representation stabilizes, a similar function should be provided for blocks.

Folds

foldGraphNodes :: forall n a. (forall e x. n e x -> a -> a) -> forall e x. Graph n e x -> a -> a Source

Fold a function over every node in a graph. The fold function must be polymorphic in the shape of the nodes.

Extracting Labels

labelsDefined :: forall block n e x. NonLocal (block n) => Graph' block n e x -> LabelSet Source

labelsUsed :: forall block n e x. NonLocal (block n) => Graph' block n e x -> LabelSet Source

externalEntryLabels :: forall n. NonLocal n => LabelMap (Block n C C) -> LabelSet Source

Depth-first traversals

postorder_dfs :: NonLocal (block n) => Graph' block n O x -> [block n C C] Source

Traversal: postorder_dfs returns a list of blocks reachable from the entry of enterable graph. The entry and exit are *not* included. The list has the following property:

Say a "back reference" exists if one of a block's control-flow successors precedes it in the output list

Then there are as few back references as possible

The output is suitable for use in a forward dataflow problem. For a backward problem, simply reverse the list. (postorder_dfs is sufficiently tricky to implement that one doesn't want to try and maintain both forward and backward versions.)

postorder_dfs_from :: (NonLocal block, LabelsPtr b) => LabelMap (block C C) -> b -> [block C C] Source

postorder_dfs_from_except :: forall block e. (NonLocal block, LabelsPtr e) => LabelMap (block C C) -> e -> LabelSet -> [block C C] Source

preorder_dfs :: NonLocal (block n) => Graph' block n O x -> [block n C C] Source

preorder_dfs_from_except :: forall block e. (NonLocal block, LabelsPtr e) => LabelMap (block C C) -> e -> LabelSet -> [block C C] Source

class LabelsPtr l where Source

Shapes

data O Source

Used at the type level to indicate an "open" structure with a unique, unnamed control-flow edge flowing in or out. Fallthrough and concatenation are permitted at an open point.

data C Source

Used at the type level to indicate a "closed" structure which supports control transfer only through the use of named labels---no "fallthrough" is permitted. The number of control-flow edges is unconstrained.

data MaybeO ex t where Source

Maybe type indexed by open/closed

data MaybeC ex t where Source

Maybe type indexed by closed/open

type family IndexedCO ex a b :: * Source

Either type indexed by closed/open using type families

data Shape ex where Source

Dynamic shape value

Blocks

data Block n e x where Source

A sequence of nodes. May be any of four shapes (OO, OC, CO, CC). Open at the entry means single entry, mutatis mutandis for exit. A closedclosed block is a basic/ block and can't be extended further. Clients should avoid manipulating blocks and should stick to either nodes or graphs.

Predicates on Blocks

isEmptyBlock :: Block n e x -> Bool Source

Constructing blocks

emptyBlock :: Block n O O Source

blockCons :: n O O -> Block n O x -> Block n O x Source

blockSnoc :: Block n e O -> n O O -> Block n e O Source

blockJoinHead :: n C O -> Block n O x -> Block n C x Source

blockJoinTail :: Block n e O -> n O C -> Block n e C Source

blockJoin :: n C O -> Block n O O -> n O C -> Block n C C Source

blockJoinAny :: (MaybeC e (n C O), Block n O O, MaybeC x (n O C)) -> Block n e x Source

Convert a list of nodes to a block. The entry and exit node must or must not be present depending on the shape of the block.

blockAppend :: Block n e O -> Block n O x -> Block n e x Source

Deconstructing blocks

firstNode :: Block n C x -> n C O Source

lastNode :: Block n x C -> n O C Source

endNodes :: Block n C C -> (n C O, n O C) Source

blockSplitHead :: Block n C x -> (n C O, Block n O x) Source

blockSplitTail :: Block n e C -> (Block n e O, n O C) Source

blockSplit :: Block n C C -> (n C O, Block n O O, n O C) Source

Split a closed block into its entry node, open middle block, and exit node.

blockSplitAny :: Block n e x -> (MaybeC e (n C O), Block n O O, MaybeC x (n O C)) Source

Modifying blocks

replaceFirstNode :: Block n C x -> n C O -> Block n C x Source

replaceLastNode :: Block n x C -> n O C -> Block n x C Source

Converting to and from lists

blockToList :: Block n O O -> [n O O] Source

blockFromList :: [n O O] -> Block n O O Source

Maps and folds

mapBlock :: (forall e x. n e x -> n' e x) -> Block n e x -> Block n' e x Source

map a function over the nodes of a Block

mapBlock' :: (forall e x. n e x -> n' e x) -> Block n e x -> Block n' e x Source

A strict mapBlock

mapBlock3' :: forall n n' e x. (n C O -> n' C O, n O O -> n' O O, n O C -> n' O C) -> Block n e x -> Block n' e x Source

map over a block, with different functions to apply to first nodes, middle nodes and last nodes respectively. The map is strict.

foldBlockNodesF :: forall n a. (forall e x. n e x -> a -> a) -> forall e x. Block n e x -> IndexedCO e a a -> IndexedCO x a a Source

foldBlockNodesF3 :: forall n a b c. (n C O -> a -> b, n O O -> b -> b, n O C -> b -> c) -> forall e x. Block n e x -> IndexedCO e a b -> IndexedCO x c b Source

Fold a function over every node in a block, forward or backward. The fold function must be polymorphic in the shape of the nodes.

foldBlockNodesB :: forall n a. (forall e x. n e x -> a -> a) -> forall e x. Block n e x -> IndexedCO x a a -> IndexedCO e a a Source

foldBlockNodesB3 :: forall n a b c. (n C O -> b -> c, n O O -> b -> b, n O C -> a -> b) -> forall e x. Block n e x -> IndexedCO x a b -> IndexedCO e c b Source

Biasing

frontBiasBlock :: Block n e x -> Block n e x Source

A block is "front biased" if the left child of every concatenation operation is a node, not a general block; a front-biased block is analogous to an ordinary list. If a block is front-biased, then its nodes can be traversed from front to back without general recusion; tail recursion suffices. Not all shapes can be front-biased; a closed/open block is inherently back-biased.

backBiasBlock :: Block n e x -> Block n e x Source

A block is "back biased" if the right child of every concatenation operation is a node, not a general block; a back-biased block is analogous to a snoc-list. If a block is back-biased, then its nodes can be traversed from back to back without general recusion; tail recursion suffices. Not all shapes can be back-biased; an open/closed block is inherently front-biased.

data AGraph n e x Source

The type of abstract graphs. Offers extra "smart constructors" that may consume fresh labels during construction.

graphOfAGraph :: AGraph n e x -> forall m. UniqueMonad m => m (Graph n e x) Source

Take an abstract AGraph and make a concrete (if monadic) Graph.

aGraphOfGraph :: Graph n e x -> AGraph n e x Source

Take a graph and make it abstract.

(<*>) :: (GraphRep g, NonLocal n) => g n e O -> g n O x -> g n e x infixl 3 Source

Concatenate two graphs; control flows from left to right.

(|*><*|) :: (GraphRep g, NonLocal n) => g n e C -> g n C x -> g n e x infixl 2 Source

Splice together two graphs at a closed point; nothing is known about control flow.

catGraphs :: (GraphRep g, NonLocal n) => [g n O O] -> g n O O Source

Conveniently concatenate a sequence of open/open graphs using <*>.

addEntrySeq :: NonLocal n => AGraph n O C -> AGraph n C x -> AGraph n O x Source

addExitSeq :: NonLocal n => AGraph n e C -> AGraph n C O -> AGraph n e O Source

addBlocks :: HooplNode n => AGraph n e x -> AGraph n C C -> AGraph n e x Source

Extend an existing AGraph with extra basic blocks "out of line". No control flow is implied. Simon PJ should give example use case.

unionBlocks :: NonLocal n => AGraph n C C -> AGraph n C C -> AGraph n C C Source

emptyGraph :: GraphRep g => g n O O Source

An empty graph that is open at entry and exit. It is the left and right identity of <*>.

emptyClosedGraph :: GraphRep g => g n C C Source

An empty graph that is closed at entry and exit. It is the left and right identity of |*><*|.

withFresh :: Uniques u => (u -> AGraph n e x) -> AGraph n e x Source

mkFirst :: GraphRep g => n C O -> g n C O Source

Create a graph from a first node

mkMiddle :: GraphRep g => n O O -> g n O O Source

Create a graph from a middle node

mkMiddles :: (GraphRep g, NonLocal n) => [n O O] -> g n O O Source

Conveniently concatenate a sequence of middle nodes to form an open/open graph.

mkLast :: GraphRep g => n O C -> g n O C Source

Create a graph from a last node

mkBranch :: (GraphRep g, HooplNode n) => Label -> g n O C Source

Create a graph that branches to a label

mkLabel :: (GraphRep g, HooplNode n) => Label -> g n C O Source

Create a graph that defines a label

mkWhileDo Source

class IfThenElseable x where Source

mkEntry :: GraphRep g => Block n O C -> g n O C Source

Create a graph containing only an entry sequence

mkExit :: GraphRep g => Block n C O -> g n C O Source

Create a graph containing only an exit sequence

class NonLocal n => HooplNode n where Source

For some graph-construction operations and some optimizations, Hoopl must be able to create control-flow edges using a given node type n.

Utilities for clients

firstXfer :: NonLocal n => (n C O -> f -> f) -> n C O -> FactBase f -> f Source

A utility function so that a transfer function for a first node can be given just a fact; we handle the lookup. This function is planned to be made obsolete by changes in the dataflow interface.

distributeXfer :: NonLocal n => DataflowLattice f -> (n O C -> f -> f) -> n O C -> f -> FactBase f Source

This utility function handles a common case in which a transfer function produces a single fact out of a last node, which is then distributed over the outgoing edges.

distributeFact :: NonLocal n => n O C -> f -> FactBase f Source

This utility function handles a common case in which a transfer function for a last node takes the incoming fact unchanged and simply distributes that fact over the outgoing edges.

distributeFactBwd :: NonLocal n => n C O -> f -> FactBase f Source

This utility function handles a common case in which a backward transfer function takes the incoming fact unchanged and tags it with the node's label.

successorFacts :: NonLocal n => n O C -> FactBase f -> [f] Source

List of (unlabelled) facts from the successors of a last node

joinFacts :: DataflowLattice f -> Label -> [f] -> f Source

Join a list of facts.

joinOutFacts :: NonLocal node => DataflowLattice f -> node O C -> FactBase f -> f Source

joinMaps :: Ord k => JoinFun v -> JoinFun (Map k v) Source

It's common to represent dataflow facts as a map from variables to some fact about the locations. For these maps, the join operation on the map can be expressed in terms of the join on each element of the codomain:

analyzeAndRewriteFwdBody :: forall m n f entries. (CheckpointMonad m, NonLocal n, LabelsPtr entries) => FwdPass m n f -> entries -> Body n -> FactBase f -> m (Body n, FactBase f) Source

Forward dataflow analysis and rewriting for the special case of a Body. A set of entry points must be supplied; blocks not reachable from the set are thrown away.

analyzeAndRewriteBwdBody :: forall m n f entries. (CheckpointMonad m, NonLocal n, LabelsPtr entries) => BwdPass m n f -> entries -> Body n -> FactBase f -> m (Body n, FactBase f) Source

Backward dataflow analysis and rewriting for the special case of a Body. A set of entry points must be supplied; blocks not reachable from the set are thrown away.

analyzeAndRewriteFwdOx :: forall m n f x. (CheckpointMonad m, NonLocal n) => FwdPass m n f -> Graph n O x -> f -> m (Graph n O x, FactBase f, MaybeO x f) Source

Forward dataflow analysis and rewriting for the special case of a graph open at the entry. This special case relieves the client from having to specify a type signature for NothingO, which beginners might find confusing and experts might find annoying.

analyzeAndRewriteBwdOx :: forall m n f x. (CheckpointMonad m, NonLocal n) => BwdPass m n f -> Graph n O x -> Fact x f -> m (Graph n O x, FactBase f, f) Source

Backward dataflow analysis and rewriting for the special case of a graph open at the entry. This special case relieves the client from having to specify a type signature for NothingO, which beginners might find confusing and experts might find annoying.

class IsSet set where Source

setInsertList :: IsSet set => [ElemOf set] -> set -> set Source

setDeleteList :: IsSet set => [ElemOf set] -> set -> set Source

setUnions :: IsSet set => [set] -> set Source

class IsMap map where Source

mapInsertList :: IsMap map => [(KeyOf map, a)] -> map a -> map a Source

mapDeleteList :: IsMap map => [KeyOf map] -> map a -> map a Source

mapUnions :: IsMap map => [map a] -> map a Source

class Monad m => CheckpointMonad m where Source

Obeys the following law: for all m do { s <- checkpoint; m; restart s } == return ()

data DataflowLattice a Source

A transfer function might want to use the logging flag to control debugging, as in for example, it updates just one element in a big finite map. We don't want Hoopl to show the whole fact, and only the transfer function knows exactly what changed.

type JoinFun a = Label -> OldFact a -> NewFact a -> (ChangeFlag, a) Source

newtype OldFact a Source

newtype NewFact a Source

type family Fact x f :: * Source

mkFactBase :: forall f. DataflowLattice f -> [(Label, f)] -> FactBase f Source

mkFactBase creates a FactBase from a list of (Label, fact) pairs. If the same label appears more than once, the relevant facts are joined.

data ChangeFlag Source

changeIf :: Bool -> ChangeFlag Source

data FwdPass m n f Source

newtype FwdTransfer n f Source

mkFTransfer :: (forall e x. n e x -> f -> Fact x f) -> FwdTransfer n f Source

mkFTransfer3 :: (n C O -> f -> f) -> (n O O -> f -> f) -> (n O C -> f -> FactBase f) -> FwdTransfer n f Source

newtype FwdRewrite m n f Source

mkFRewrite :: FuelMonad m => (forall e x. n e x -> f -> m (Maybe (Graph n e x))) -> FwdRewrite m n f Source

Functions passed to mkFRewrite should not be aware of the fuel supply. The result returned by mkFRewrite respects fuel.

mkFRewrite3 :: forall m n f. FuelMonad m => (n C O -> f -> m (Maybe (Graph n C O))) -> (n O O -> f -> m (Maybe (Graph n O O))) -> (n O C -> f -> m (Maybe (Graph n O C))) -> FwdRewrite m n f Source

Functions passed to mkFRewrite3 should not be aware of the fuel supply. The result returned by mkFRewrite3 respects fuel.

noFwdRewrite :: Monad m => FwdRewrite m n f Source

wrapFR Source

wrapFR2 Source

data BwdPass m n f Source

newtype BwdTransfer n f Source

mkBTransfer :: (forall e x. n e x -> Fact x f -> f) -> BwdTransfer n f Source

mkBTransfer3 :: (n C O -> f -> f) -> (n O O -> f -> f) -> (n O C -> FactBase f -> f) -> BwdTransfer n f Source

wrapBR Source

wrapBR2 Source

newtype BwdRewrite m n f Source

mkBRewrite :: FuelMonad m => (forall e x. n e x -> Fact x f -> m (Maybe (Graph n e x))) -> BwdRewrite m n f Source

Functions passed to mkBRewrite should not be aware of the fuel supply. The result returned by mkBRewrite respects fuel.

mkBRewrite3 :: forall m n f. FuelMonad m => (n C O -> f -> m (Maybe (Graph n C O))) -> (n O O -> f -> m (Maybe (Graph n O O))) -> (n O C -> FactBase f -> m (Maybe (Graph n O C))) -> BwdRewrite m n f Source

Functions passed to mkBRewrite3 should not be aware of the fuel supply. The result returned by mkBRewrite3 respects fuel.

noBwdRewrite :: Monad m => BwdRewrite m n f Source

analyzeAndRewriteFwd :: forall m n f e x entries. (CheckpointMonad m, NonLocal n, LabelsPtr entries) => FwdPass m n f -> MaybeC e entries -> Graph n e x -> Fact e f -> m (Graph n e x, FactBase f, MaybeO x f) Source

if the graph being analyzed is open at the entry, there must be no other entry point, or all goes horribly wrong...

analyzeAndRewriteBwd :: (CheckpointMonad m, NonLocal n, LabelsPtr entries) => BwdPass m n f -> MaybeC e entries -> Graph n e x -> Fact x f -> m (Graph n e x, FactBase f, MaybeO e f) Source

if the graph being analyzed is open at the exit, I don't quite understand the implications of possible other exits

Respecting Fuel

A value of type FwdRewrite or BwdRewrite respects fuel if any function contained within the value satisfies the following properties:

• When fuel is exhausted, it always returns Nothing.
• When it returns Just g rw, it consumes exactly one unit of fuel, and new rewrite rw also respects fuel.

Provided that functions passed to mkFRewrite, mkFRewrite3, mkBRewrite, and mkBRewrite3 are not aware of the fuel supply, the results respect fuel.

It is an unchecked run-time error for the argument passed to wrapFR, wrapFR2, wrapBR, or warpBR2 to return a function that does not respect fuel.

data Label Source

freshLabel :: UniqueMonad m => m Label Source

data LabelSet Source

data LabelMap v Source

type FactBase f = LabelMap f Source

noFacts :: FactBase f Source

lookupFact :: Label -> FactBase f -> Maybe f Source

uniqueToLbl :: Unique -> Label Source

lblToUnique :: Label -> Unique Source

data Pointed t b a where Source

Adds top, bottom, or both to help form a lattice

The type parameters t and b are used to say whether top and bottom elements have been added. The analogy with Block is nearly exact:

• A Block is closed at the entry if and only if it has a first node; a Pointed is closed at the top if and only if it has a top element.
• A Block is closed at the exit if and only if it has a last node; a Pointed is closed at the bottom if and only if it has a bottom element.

We thus have four possible types, of which three are interesting:

Pointed C C a

Type a extended with both top and bottom elements.

Pointed C O a

Type a extended with a top element only. (Presumably a comes equipped with a bottom element of its own.)

Pointed O C a

Type a extended with a bottom element only.

Pointed O O a

Isomorphic to a, and therefore not interesting.

The advantage of all this GADT-ishness is that the constructors Bot, Top, and PElem can all be used polymorphically.

A 'Pointed t b' type is an instance of Functor and Show.

addPoints :: String -> JoinFun a -> DataflowLattice (Pointed t C a) Source

Given a join function and a name, creates a semi lattice by adding a bottom element, and possibly a top element also. A specialized version of addPoints'.

addPoints' :: forall a t. String -> (Label -> OldFact a -> NewFact a -> (ChangeFlag, Pointed t C a)) -> DataflowLattice (Pointed t C a) Source

A more general case for creating a new lattice

addTop :: DataflowLattice a -> DataflowLattice (WithTop a) Source

Given a join function and a name, creates a semi lattice by adding a top element but no bottom element. Caller must supply the bottom element.

addTop' :: forall a. String -> a -> (Label -> OldFact a -> NewFact a -> (ChangeFlag, WithTop a)) -> DataflowLattice (WithTop a) Source

A more general case for creating a new lattice

liftJoinTop :: JoinFun a -> JoinFun (WithTop a) Source

extendJoinDomain :: forall a. (Label -> OldFact a -> NewFact a -> (ChangeFlag, WithTop a)) -> JoinFun (WithTop a) Source

type WithTop a = Pointed C O a Source

Type a with a top element adjoined

type WithBot a = Pointed O C a Source

Type a with a bottom element adjoined

type WithTopAndBot a = Pointed C C a Source

Type a with top and bottom elements adjoined

thenFwdRw :: forall m n f. Monad m => FwdRewrite m n f -> FwdRewrite m n f -> FwdRewrite m n f Source

deepFwdRw3 :: FuelMonad m => (n C O -> f -> m (Maybe (Graph n C O))) -> (n O O -> f -> m (Maybe (Graph n O O))) -> (n O C -> f -> m (Maybe (Graph n O C))) -> FwdRewrite m n f Source

deepFwdRw :: FuelMonad m => (forall e x. n e x -> f -> m (Maybe (Graph n e x))) -> FwdRewrite m n f Source

iterFwdRw :: forall m n f. Monad m => FwdRewrite m n f -> FwdRewrite m n f Source

thenBwdRw :: forall m n f. Monad m => BwdRewrite m n f -> BwdRewrite m n f -> BwdRewrite m n f Source

deepBwdRw3 :: FuelMonad m => (n C O -> f -> m (Maybe (Graph n C O))) -> (n O O -> f -> m (Maybe (Graph n O O))) -> (n O C -> FactBase f -> m (Maybe (Graph n O C))) -> BwdRewrite m n f Source

deepBwdRw :: FuelMonad m => (forall e x. n e x -> Fact x f -> m (Maybe (Graph n e x))) -> BwdRewrite m n f Source

iterBwdRw :: forall m n f. Monad m => BwdRewrite m n f -> BwdRewrite m n f Source

pairFwd :: forall m n f f'. Monad m => FwdPass m n f -> FwdPass m n f' -> FwdPass m n (f, f') Source

pairBwd :: forall m n f f'. Monad m => BwdPass m n f -> BwdPass m n f' -> BwdPass m n (f, f') Source

pairLattice :: forall f f'. DataflowLattice f -> DataflowLattice f' -> DataflowLattice (f, f') Source

type Fuel = Int Source

infiniteFuel :: Fuel Source

fuelRemaining :: FuelMonad m => m Fuel Source

Find out how much fuel remains after a computation. Can be subtracted from initial fuel to get total consumption.

withFuel :: FuelMonad m => Maybe a -> m (Maybe a) Source

class Monad m => FuelMonad m where Source

class FuelMonadT fm where Source

data CheckingFuelMonad m a Source

data InfiniteFuelMonad m a Source

type SimpleFuelMonad = CheckingFuelMonad SimpleUniqueMonad Source

type Unique = Int Source

intToUnique :: Int -> Unique Source

data UniqueSet Source

data UniqueMap v Source

class Monad m => UniqueMonad m where Source

data SimpleUniqueMonad a Source

runSimpleUniqueMonad :: SimpleUniqueMonad a -> a Source

data UniqueMonadT m a Source

runUniqueMonadT :: Monad m => UniqueMonadT m a -> m a Source

uniqueToInt :: Unique -> Int Source

type TraceFn = forall a. String -> a -> a Source

debugFwdJoins :: forall m n f. Show f => TraceFn -> ChangePred -> FwdPass m n f -> FwdPass m n f Source

Debugging combinators: Each combinator takes a dataflow pass and produces a dataflow pass that can output debugging messages. You provide the function, we call it with the applicable message.

The most common use case is probably to:

1. import Trace
2. pass trace as the 1st argument to the debug combinator
3. pass 'const true' as the 2nd argument to the debug combinator

There are two kinds of debugging messages for a join, depending on whether the join is higher in the lattice than the old fact: 1. If the join is higher, we show: + JoinL: f1 join f2 = f' where: + indicates a change L is the label where the join takes place f1 is the old fact at the label f2 is the new fact we are joining to f1 f' is the result of the join 2. _ JoinL: f2 <= f1 where: _ indicates no change L is the label where the join takes place f1 is the old fact at the label (which remains unchanged) f2 is the new fact we joined with f1

debugBwdJoins :: forall m n f. Show f => TraceFn -> ChangePred -> BwdPass m n f -> BwdPass m n f Source

debugFwdTransfers :: forall m n f. Show f => TraceFn -> ShowN n -> FPred n f -> FwdPass m n f -> FwdPass m n f Source

debugBwdTransfers :: forall m n f. Show f => TraceFn -> ShowN n -> BPred n f -> BwdPass m n f -> BwdPass m n f Source

showGraph :: forall n e x. NonLocal n => Showing n -> Graph n e x -> String Source

showFactBase :: Show f => FactBase f -> String Source