GHC.Cmm.DebugBlock

Documentation

data DebugBlock

Debug information about a block of code. Ticks scope over nested blocks.

Constructors

DebugBlock

Fields

• dblProcedure :: !Label

  Entry label of containing proc

• dblLabel :: !Label

  Hoopl label

• dblCLabel :: !CLabel

  Output label

• dblHasInfoTbl :: !Bool

  Has an info table?

• dblParent :: !(Maybe DebugBlock)

  The parent of this proc. See Note [Splitting DebugBlocks]

• dblTicks :: ![CmmTickish]

  Ticks defined in this block

• dblSourceTick :: !(Maybe CmmTickish)

  Best source tick covering block

• dblPosition :: !(Maybe Int)

  Output position relative to other blocks. Nothing means the block was optimized out

• dblUnwind :: [UnwindPoint]
• dblBlocks :: ![DebugBlock]

  Nested blocks

Instances

OutputableP env CLabel => OutputableP env DebugBlock

Defined in GHC.Cmm.DebugBlock

Methods

pdoc :: env -> DebugBlock -> SDoc

cmmDebugGen :: ModLocation -> RawCmmGroup -> [DebugBlock]

Extract debug data from a group of procedures. We will prefer source notes that come from the given module (presumably the module that we are currently compiling).

cmmDebugLabels :: (i -> Bool) -> GenCmmGroup d g (ListGraph i) -> [Label]

cmmDebugLink :: [Label] -> LabelMap [UnwindPoint] -> [DebugBlock] -> [DebugBlock]

Sets position and unwind table fields in the debug block tree according to native generated code.

debugToMap :: [DebugBlock] -> LabelMap DebugBlock

Converts debug blocks into a label map for easier lookups

Unwinding information

type UnwindTable = Map GlobalReg (Maybe UnwindExpr)

Maps registers to expressions that yield their "old" values further up the stack. Most interesting for the stack pointer Sp, but might be useful to document saved registers, too. Note that a register's value will be Nothing when the register's previous value cannot be reconstructed.

data UnwindPoint

A label associated with an UnwindTable

Constructors

UnwindPoint !CLabel !UnwindTable

Instances

OutputableP env CLabel => OutputableP env UnwindPoint

Defined in GHC.Cmm.DebugBlock

Methods

pdoc :: env -> UnwindPoint -> SDoc

data UnwindExpr

Expressions, used for unwind information

Constructors

UwConst !Int

literal value

UwReg !GlobalReg !Int

register plus offset

UwDeref UnwindExpr

pointer dereferencing

UwLabel CLabel

UwPlus UnwindExpr UnwindExpr

UwMinus UnwindExpr UnwindExpr

UwTimes UnwindExpr UnwindExpr

Instances

Eq UnwindExpr

Defined in GHC.Cmm.DebugBlock

Methods

(==) :: UnwindExpr -> UnwindExpr -> Bool

(/=) :: UnwindExpr -> UnwindExpr -> Bool

OutputableP env CLabel => OutputableP env UnwindExpr

Defined in GHC.Cmm.DebugBlock

Methods

pdoc :: env -> UnwindExpr -> SDoc

toUnwindExpr :: Platform -> CmmExpr -> UnwindExpr

Conversion of Cmm expressions to unwind expressions. We check for unsupported operator usages and simplify the expression as far as possible.