Documentation

data BrokenBlock Source

Similar to a CmmBlock with a little extra information to help the CPS analysis.

Constructors

BrokenBlock

Fields

brokenBlockId :: BlockId: The block's label like a CmmBasicBlock
brokenBlockEntry :: BlockEntryInfo: Ways this block can be entered
brokenBlockStmts :: [CmmStmt]: Body like a CmmBasicBlock (but without the last statement)
brokenBlockTargets :: [BlockId]: Blocks that this block could branch to either by conditional branches or via the last statement
brokenBlockExit :: FinalStmt: The final statement of the block

data BlockEntryInfo Source

How a block could be entered See Note [An example of CPS conversion]

Constructors

FunctionEntry CmmInfo CLabel CmmFormals	Block is the beginning of a function, parameters are: 1. Function header info 2. The function name 3. Aguments to function Only the formal parameters are live
ContinuationEntry CmmFormals C_SRT Bool	Return point of a function call, parameters are: 1. return values (argument to continuation) 2. SRT for the continuation's info table 3. True = GC block so ignore stack size Live variables, other than the return values, are on the stack
ControlEntry	Any other kind of block. Only entered due to control flow.

data FinalStmt Source

Final statement in a BlokenBlock. Constructors and arguments match those in Cmm, but are restricted to branches, returns, jumps, calls and switches

Constructors

FinalBranch BlockId	Same as `CmmBranch`. Target must be a ControlEntry
FinalReturn HintedCmmActuals	Same as `CmmReturn`. Parameter is the return values.
FinalJump CmmExpr HintedCmmActuals	Same as `CmmJump`. Parameters: 1. The function to call, 2. Arguments of the call
FinalCall BlockId CmmCallTarget HintedCmmFormals HintedCmmActuals C_SRT CmmReturnInfo Bool	Same as `CmmCallee` followed by `CmmGoto`. Parameters: 1. Target of the `CmmGoto` (must be a `ContinuationEntry`) 2. The function to call 3. Results from call (redundant with ContinuationEntry) 4. Arguments to call 5. SRT for the continuation's info table 6. Does the function return? 7. True = GC block so ignore stack size
FinalSwitch CmmExpr [Maybe BlockId]	Same as a `CmmSwitch`. Paremeters: 1. Scrutinee (zero based) 2. Targets

breakBlock Source

Arguments

:: [BlockId]	Any GC blocks that should be special
-> [Unique]	An infinite list of uniques to create names of the new blocks with
-> CmmBasicBlock	Input block to break apart
-> BlockEntryInfo	Info for the first created `BrokenBlock`
-> ([(BlockId, ContFormat)], [BrokenBlock])

Takes a CmmBasicBlock and breaks it up into a list of BrokenBlock by splitting on each CmmCall in the CmmBasicBlock.

cmmBlockFromBrokenBlock :: BrokenBlock -> CmmBasicBlock Source

Convert from a BrokenBlock back to an equivalent CmmBasicBlock Needed by liveness analysis

blocksToBlockEnv :: [BrokenBlock] -> BlockEnv BrokenBlock Source

Build a mapping so we can lookup a BrokenBlock by its BlockId

adaptBlockToFormat :: [(BlockId, ContFormat)] -> Unique -> BrokenBlock -> [BrokenBlock]Source

selectContinuations :: [(BlockId, ContFormat)] -> [(BlockId, ContFormat)]Source

data ContFormat Source

Instances

Eq ContFormat

makeContinuationEntries :: [(BlockId, ContFormat)] -> BrokenBlock -> BrokenBlock Source