ghc-7.0.3: The GHC API

MkZipCfg

Synopsis

- data AGraph m l
- (<*>) :: AGraph m l -> AGraph m l -> AGraph m l
- catAGraphs :: [AGraph m l] -> AGraph m l
- freshBlockId :: MonadUnique m => String -> m BlockId
- emptyAGraph :: AGraph m l
- withFreshLabel :: String -> (BlockId -> AGraph m l) -> AGraph m l
- withUnique :: (Unique -> AGraph m l) -> AGraph m l
- mkMiddle :: m -> AGraph m l
- mkMiddles :: [m] -> AGraph m l
- mkLast :: (Outputable m, Outputable l, LastNode l) => l -> AGraph m l
- mkZTail :: (Outputable m, Outputable l, LastNode l) => ZTail m l -> AGraph m l
- mkBranch :: (Outputable m, Outputable l, LastNode l) => BlockId -> AGraph m l
- mkLabel :: LastNode l => BlockId -> AGraph m l
- mkIfThenElse :: (Outputable m, Outputable l, LastNode l) => (BlockId -> BlockId -> AGraph m l) -> AGraph m l -> AGraph m l -> AGraph m l
- mkWhileDo :: (Outputable m, Outputable l, LastNode l) => (BlockId -> BlockId -> AGraph m l) -> AGraph m l -> AGraph m l
- outOfLine :: (LastNode l, Outputable m, Outputable l) => AGraph m l -> AGraph m l
- emptyGraph :: Graph m l
- graphOfMiddles :: [m] -> Graph m l
- graphOfZTail :: ZTail m l -> Graph m l
- lgraphOfAGraph :: AGraph m l -> UniqSM (LGraph m l)
- graphOfAGraph :: AGraph m l -> UniqSM (Graph m l)
- labelAGraph :: BlockId -> AGraph m l -> UniqSM (LGraph m l)
- pprAGraph :: (Outputable m, LastNode l, Outputable l) => AGraph m l -> UniqSM SDoc

# Documentation

data AGraph m l

(<*>) :: AGraph m l -> AGraph m l -> AGraph m l

catAGraphs :: [AGraph m l] -> AGraph m l

freshBlockId :: MonadUnique m => String -> m BlockId

The string argument to `freshBlockId` was originally helpful in debugging the Quick C-- compiler, so I have kept it here even though at present it is thrown away at this spot---there's no reason a BlockId couldn't one day carry a string.

emptyAGraph :: AGraph m l

A graph is built up by splicing together graphs each containing a single node (where a label is considered a `first` node. The empty graph is a left and right unit for splicing. All of the AGraph constructors (even complex ones like `mkIfThenElse`, as well as the splicing operation *, are constant-time operations.

withFreshLabel :: String -> (BlockId -> AGraph m l) -> AGraph m l

This function provides access to fresh labels without requiring clients to be programmed monadically.

withUnique :: (Unique -> AGraph m l) -> AGraph m l

mkMiddle :: m -> AGraph m l

mkMiddles :: [m] -> AGraph m l

mkLast :: (Outputable m, Outputable l, LastNode l) => l -> AGraph m l

mkZTail :: (Outputable m, Outputable l, LastNode l) => ZTail m l -> AGraph m l

mkBranch :: (Outputable m, Outputable l, LastNode l) => BlockId -> AGraph m l

mkLabel :: LastNode l => BlockId -> AGraph m l

mkIfThenElse :: (Outputable m, Outputable l, LastNode l) => (BlockId -> BlockId -> AGraph m l) -> AGraph m l -> AGraph m l -> AGraph m l

For the structured control-flow constructs, a condition is represented as a function that takes as arguments the labels to goto on truth or falsehood.

mkIfThenElse mk_cond then else = (mk_cond L1 L2) * L1: then * goto J * L2: else * goto J * J:

where L1, L2, J are fresh

mkWhileDo :: (Outputable m, Outputable l, LastNode l) => (BlockId -> BlockId -> AGraph m l) -> AGraph m l -> AGraph m l

outOfLine :: (LastNode l, Outputable m, Outputable l) => AGraph m l -> AGraph m l

The argument is an AGraph that has an empty entry sequence and no exit sequence. The result is a new AGraph that has an empty entry sequence connected to an empty exit sequence, with the original graph sitting to the side out-of-line.

Example: mkMiddle (x = 3) * outOfLine (mkLabel L * ...stuff...) * mkMiddle (y = x) Control will flow directly from x=3 to y=x; the block starting with L is on the side.

N.B. algebraically forall g g' : g * outOfLine g' == outOfLine g' * g

emptyGraph :: Graph m l

The functions below build Graphs directly; for convenience, they are included here with the rest of the constructor functions.

graphOfMiddles :: [m] -> Graph m l

graphOfZTail :: ZTail m l -> Graph m l

lgraphOfAGraph

Arguments

:: AGraph m l |
-> UniqSM (LGraph m l) | allocate a fresh label for the entry point

graphOfAGraph :: AGraph m l -> UniqSM (Graph m l)

Converting an abstract graph to a concrete form is expensive: the cost is linear in the number of nodes in the answer, plus N log N in the number of basic blocks. The conversion is also monadic because it may require the allocation of fresh, unique labels.

labelAGraph

Arguments

:: BlockId |
-> AGraph m l |
-> UniqSM (LGraph m l) | use the given BlockId as the label of the entry point

pprAGraph :: (Outputable m, LastNode l, Outputable l) => AGraph m l -> UniqSM SDoc