ghc-8.2.1: The GHC API

Safe HaskellNone




type CmmAGraph = OrdList CgStmt Source #

CmmAGraph is a chunk of code consisting of:

  • ordinary statements (assignments, stores etc.)
  • jumps
  • labels
  • out-of-line labelled blocks

The semantics is that control falls through labels and out-of-line blocks. Everything after a jump up to the next label is by definition unreachable code, and will be discarded.

Two CmmAGraphs can be stuck together with *, with the meaning that control flows from the first to the second.

A CmmAGraph can be turned into a CmmGraph (closed at both ends) by providing a label for the entry point and a tick scope; see labelAGraph.

type CmmAGraphScoped = (CmmAGraph, CmmTickScope) Source #

Unlabeled graph with tick scope

mkLabel :: BlockId -> CmmTickScope -> CmmAGraph Source #

created a sequence "goto id; id:" as an AGraph

mkMiddle :: CmmNode O O -> CmmAGraph Source #

creates an open AGraph from a given node

mkLast :: CmmNode O C -> CmmAGraph Source #

created a closed AGraph from a given node

outOfLine :: BlockId -> CmmAGraphScoped -> CmmAGraph Source #

A labelled code block; should end in a last node

lgraphOfAGraph :: CmmAGraphScoped -> UniqSM CmmGraph Source #

allocate a fresh label for the entry point

labelAGraph :: BlockId -> CmmAGraphScoped -> CmmGraph Source #

use the given BlockId as the label of the entry point

mkRawJump :: DynFlags -> CmmExpr -> UpdFrameOffset -> [GlobalReg] -> CmmAGraph Source #

A jump where the caller says what the live GlobalRegs are. Used for low-level hand-written Cmm.

mkUnwind :: GlobalReg -> CmmExpr -> CmmAGraph Source #

Construct a CmmUnwind node for the given register and unwinding expression.

data Transfer Source #