GHC.Cmm.CLabel

ghc-9.0.1: The GHC API

Safe Haskell | None
Language | Haskell2010

GHC.Cmm.CLabel

Contents

- Predicates
- Conversions

Synopsis

- data CLabel
- newtype NeedExternDecl = NeedExternDecl Bool
- data ForeignLabelSource
  - = ForeignLabelInPackage Unit
  - | ForeignLabelInExternalPackage
  - | ForeignLabelInThisPackage
- pprDebugCLabel :: CLabel -> SDoc
- mkClosureLabel :: Name -> CafInfo -> CLabel
- mkSRTLabel :: Unique -> CLabel
- mkInfoTableLabel :: Name -> CafInfo -> CLabel
- mkEntryLabel :: Name -> CafInfo -> CLabel
- mkRednCountsLabel :: Name -> CLabel
- mkConInfoTableLabel :: Name -> CafInfo -> CLabel
- mkApEntryLabel :: DynFlags -> Bool -> Int -> CLabel
- mkApInfoTableLabel :: DynFlags -> Bool -> Int -> CLabel
- mkClosureTableLabel :: Name -> CafInfo -> CLabel
- mkBytesLabel :: Name -> CLabel
- mkLocalBlockLabel :: Unique -> CLabel
- mkLocalClosureLabel :: Name -> CafInfo -> CLabel
- mkLocalInfoTableLabel :: Name -> CafInfo -> CLabel
- mkLocalClosureTableLabel :: Name -> CafInfo -> CLabel
- mkBlockInfoTableLabel :: Name -> CafInfo -> CLabel
- mkBitmapLabel :: Unique -> CLabel
- mkStringLitLabel :: Unique -> CLabel
- mkAsmTempLabel :: Uniquable a => a -> CLabel
- mkAsmTempDerivedLabel :: CLabel -> FastString -> CLabel
- mkAsmTempEndLabel :: CLabel -> CLabel
- mkAsmTempDieLabel :: CLabel -> CLabel
- mkDirty_MUT_VAR_Label :: CLabel
- mkNonmovingWriteBarrierEnabledLabel :: CLabel
- mkUpdInfoLabel :: CLabel
- mkBHUpdInfoLabel :: CLabel
- mkIndStaticInfoLabel :: CLabel
- mkMainCapabilityLabel :: CLabel
- mkMAP_FROZEN_CLEAN_infoLabel :: CLabel
- mkMAP_FROZEN_DIRTY_infoLabel :: CLabel
- mkMAP_DIRTY_infoLabel :: CLabel
- mkSMAP_FROZEN_CLEAN_infoLabel :: CLabel
- mkSMAP_FROZEN_DIRTY_infoLabel :: CLabel
- mkSMAP_DIRTY_infoLabel :: CLabel
- mkBadAlignmentLabel :: CLabel
- mkArrWords_infoLabel :: CLabel
- mkSRTInfoLabel :: Int -> CLabel
- mkTopTickyCtrLabel :: CLabel
- mkCAFBlackHoleInfoTableLabel :: CLabel
- mkRtsPrimOpLabel :: PrimOp -> CLabel
- mkRtsSlowFastTickyCtrLabel :: String -> CLabel
- mkSelectorInfoLabel :: DynFlags -> Bool -> Int -> CLabel
- mkSelectorEntryLabel :: DynFlags -> Bool -> Int -> CLabel
- mkCmmInfoLabel :: UnitId -> FastString -> CLabel
- mkCmmEntryLabel :: UnitId -> FastString -> CLabel
- mkCmmRetInfoLabel :: UnitId -> FastString -> CLabel
- mkCmmRetLabel :: UnitId -> FastString -> CLabel
- mkCmmCodeLabel :: UnitId -> FastString -> CLabel
- mkCmmDataLabel :: UnitId -> NeedExternDecl -> FastString -> CLabel
- mkRtsCmmDataLabel :: FastString -> CLabel
- mkCmmClosureLabel :: UnitId -> FastString -> CLabel
- mkRtsApFastLabel :: FastString -> CLabel
- mkPrimCallLabel :: PrimCall -> CLabel
- mkForeignLabel :: FastString -> Maybe Int -> ForeignLabelSource -> FunctionOrData -> CLabel
- addLabelSize :: CLabel -> Int -> CLabel
- foreignLabelStdcallInfo :: CLabel -> Maybe Int
- isBytesLabel :: CLabel -> Bool
- isForeignLabel :: CLabel -> Bool
- isSomeRODataLabel :: CLabel -> Bool
- isStaticClosureLabel :: CLabel -> Bool
- mkCCLabel :: CostCentre -> CLabel
- mkCCSLabel :: CostCentreStack -> CLabel
- data DynamicLinkerLabelInfo
  - = CodeStub
  - | SymbolPtr
  - | GotSymbolPtr
  - | GotSymbolOffset
- mkDynamicLinkerLabel :: DynamicLinkerLabelInfo -> CLabel -> CLabel
- dynamicLinkerLabelInfo :: CLabel -> Maybe (DynamicLinkerLabelInfo, CLabel)
- mkPicBaseLabel :: CLabel
- mkDeadStripPreventer :: CLabel -> CLabel
- mkHpcTicksLabel :: Module -> CLabel
- hasCAF :: CLabel -> Bool
- needsCDecl :: CLabel -> Bool
- maybeLocalBlockLabel :: CLabel -> Maybe BlockId
- externallyVisibleCLabel :: CLabel -> Bool
- isMathFun :: CLabel -> Bool
- isCFunctionLabel :: CLabel -> Bool
- isGcPtrLabel :: CLabel -> Bool
- labelDynamic :: NCGConfig -> Module -> CLabel -> Bool
- isLocalCLabel :: Module -> CLabel -> Bool
- mayRedirectTo :: CLabel -> CLabel -> Bool
- toClosureLbl :: CLabel -> CLabel
- toSlowEntryLbl :: CLabel -> CLabel
- toEntryLbl :: CLabel -> CLabel
- toInfoLbl :: CLabel -> CLabel
- hasHaskellName :: CLabel -> Maybe Name
- pprCLabel :: DynFlags -> CLabel -> SDoc
- isInfoTableLabel :: CLabel -> Bool
- isConInfoTableLabel :: CLabel -> Bool
- isIdLabel :: CLabel -> Bool
- isTickyLabel :: CLabel -> Bool

# Documentation

data CLabel Source #

`CLabel` is an abstract type that supports the following operations:

- Pretty printing
- In a C file, does it need to be declared before use? (i.e. is it guaranteed to be already in scope in the places we need to refer to it?)
- If it needs to be declared, what type (code or data) should it be declared to have?
- Is it visible outside this object file or not?
- Is it "dynamic" (see details below)
- Eq and Ord, so that we can make sets of CLabels (currently only used in outputting C as far as I can tell, to avoid generating more than one declaration for any given label).
- Converting an info table label into an entry label.

CLabel usage is a bit messy in GHC as they are used in a number of different contexts:

- By the C-- AST to identify labels
- By the unregisterised C code generator ("PprC") for naming functions (hence the name `CLabel`)
- By the native and LLVM code generators to identify labels

For extra fun, each of these uses a slightly different subset of constructors (e.g. `AsmTempLabel` and `AsmTempDerivedLabel` are used only in the NCG and LLVM backends).

In general, we use `IdLabel` to represent Haskell things early in the pipeline. However, later optimization passes will often represent blocks they create with `LocalBlockLabel` where there is no obvious `Name` to hang off the label.

#### Instances

Instances details

Eq CLabel # |
Instance details Defined in GHC.Cmm.CLabel Methods (==) :: CLabel -> CLabel -> Bool # (/=) :: CLabel -> CLabel -> Bool #
Ord CLabel # |
Instance details Defined in GHC.Cmm.CLabel Methods compare :: CLabel -> CLabel -> Ordering # (<) :: CLabel -> CLabel -> Bool # (<=) :: CLabel -> CLabel -> Bool # (>) :: CLabel -> CLabel -> Bool # (>=) :: CLabel -> CLabel -> Bool # max :: CLabel -> CLabel -> CLabel # min :: CLabel -> CLabel -> CLabel #
Outputable CLabel # |
Instance details Defined in GHC.Cmm.CLabel Methods ppr :: CLabel -> SDoc Source # pprPrec :: Rational -> CLabel -> SDoc Source #

newtype NeedExternDecl Source #

Indicate if GHC.CmmToC has to generate an extern declaration for the label (e.g. "extern StgWordArray(foo)"). The type is fixed to StgWordArray.

Symbols from the RTS don't need "extern" declarations because they are exposed via "includes/Stg.h" with the appropriate type. See `needsCDecl`.

The fixed StgWordArray type led to "conflicting types" issues with user provided Cmm files (not in the RTS) that declare data of another type (#15467 and test for #17920). Hence the Cmm parser considers that labels in data sections don't need the "extern" declaration (just add one explicitly if you need it).

See https://gitlab.haskell.org/ghc/ghc/-/wikis/commentary/compiler/backends/ppr-c#prototypes for why extern declaration are needed at all.

Constructors

NeedExternDecl Bool |

#### Instances

Instances details

Eq NeedExternDecl # |
Instance details Defined in GHC.Cmm.CLabel Methods (==) :: NeedExternDecl -> NeedExternDecl -> Bool # (/=) :: NeedExternDecl -> NeedExternDecl -> Bool #
Ord NeedExternDecl # |
Instance details Defined in GHC.Cmm.CLabel Methods compare :: NeedExternDecl -> NeedExternDecl -> Ordering # (<) :: NeedExternDecl -> NeedExternDecl -> Bool # (<=) :: NeedExternDecl -> NeedExternDecl -> Bool # (>) :: NeedExternDecl -> NeedExternDecl -> Bool # (>=) :: NeedExternDecl -> NeedExternDecl -> Bool # max :: NeedExternDecl -> NeedExternDecl -> NeedExternDecl # min :: NeedExternDecl -> NeedExternDecl -> NeedExternDecl #

data ForeignLabelSource Source #

Record where a foreign label is stored.

Constructors

ForeignLabelInPackage Unit | Label is in a named package
ForeignLabelInExternalPackage | Label is in some external, system package that doesn't also contain compiled Haskell code, and is not associated with any .hi files. We don't have to worry about Haskell code being inlined from external packages. It is safe to treat the RTS package as "external".
ForeignLabelInThisPackage | Label is in the package currently being compiled. This is only used for creating hacky tmp labels during code generation. Don't use it in any code that might be inlined across a package boundary (ie, core code) else the information will be wrong relative to the destination module.

#### Instances

Instances details

Eq ForeignLabelSource # |
Instance details Defined in GHC.Cmm.CLabel Methods (==) :: ForeignLabelSource -> ForeignLabelSource -> Bool # (/=) :: ForeignLabelSource -> ForeignLabelSource -> Bool #
Ord ForeignLabelSource # |
Instance details Defined in GHC.Cmm.CLabel Methods compare :: ForeignLabelSource -> ForeignLabelSource -> Ordering # (<) :: ForeignLabelSource -> ForeignLabelSource -> Bool # (<=) :: ForeignLabelSource -> ForeignLabelSource -> Bool # (>) :: ForeignLabelSource -> ForeignLabelSource -> Bool # (>=) :: ForeignLabelSource -> ForeignLabelSource -> Bool # max :: ForeignLabelSource -> ForeignLabelSource -> ForeignLabelSource # min :: ForeignLabelSource -> ForeignLabelSource -> ForeignLabelSource #
Outputable ForeignLabelSource # |
Instance details Defined in GHC.Cmm.CLabel Methods ppr :: ForeignLabelSource -> SDoc Source # pprPrec :: Rational -> ForeignLabelSource -> SDoc Source #

pprDebugCLabel :: CLabel -> SDoc Source #

For debugging problems with the CLabel representation. We can't make a Show instance for CLabel because lots of its components don't have instances. The regular Outputable instance only shows the label name, and not its other info.

mkClosureLabel :: Name -> CafInfo -> CLabel Source #

mkSRTLabel :: Unique -> CLabel Source #

mkInfoTableLabel :: Name -> CafInfo -> CLabel Source #

mkEntryLabel :: Name -> CafInfo -> CLabel Source #

mkRednCountsLabel :: Name -> CLabel Source #

mkConInfoTableLabel :: Name -> CafInfo -> CLabel Source #

mkApEntryLabel :: DynFlags -> Bool -> Int -> CLabel Source #

mkApInfoTableLabel :: DynFlags -> Bool -> Int -> CLabel Source #

mkClosureTableLabel :: Name -> CafInfo -> CLabel Source #

mkBytesLabel :: Name -> CLabel Source #

mkLocalBlockLabel :: Unique -> CLabel Source #

mkLocalClosureLabel :: Name -> CafInfo -> CLabel Source #

mkLocalInfoTableLabel :: Name -> CafInfo -> CLabel Source #

mkLocalClosureTableLabel :: Name -> CafInfo -> CLabel Source #

mkBlockInfoTableLabel :: Name -> CafInfo -> CLabel Source #

mkBitmapLabel :: Unique -> CLabel Source #

mkStringLitLabel :: Unique -> CLabel Source #

mkAsmTempLabel :: Uniquable a => a -> CLabel Source #

mkAsmTempDerivedLabel :: CLabel -> FastString -> CLabel Source #

mkAsmTempEndLabel :: CLabel -> CLabel Source #

mkAsmTempDieLabel :: CLabel -> CLabel Source #

Construct a label for a DWARF Debug Information Entity (DIE) describing another symbol.

mkDirty_MUT_VAR_Label :: CLabel Source #

mkNonmovingWriteBarrierEnabledLabel :: CLabel Source #

mkUpdInfoLabel :: CLabel Source #

mkBHUpdInfoLabel :: CLabel Source #

mkIndStaticInfoLabel :: CLabel Source #

mkMainCapabilityLabel :: CLabel Source #

mkMAP_FROZEN_CLEAN_infoLabel :: CLabel Source #

mkMAP_FROZEN_DIRTY_infoLabel :: CLabel Source #

mkMAP_DIRTY_infoLabel :: CLabel Source #

mkSMAP_FROZEN_CLEAN_infoLabel :: CLabel Source #

mkSMAP_FROZEN_DIRTY_infoLabel :: CLabel Source #

mkSMAP_DIRTY_infoLabel :: CLabel Source #

mkBadAlignmentLabel :: CLabel Source #

mkArrWords_infoLabel :: CLabel Source #

mkSRTInfoLabel :: Int -> CLabel Source #

mkTopTickyCtrLabel :: CLabel Source #

mkCAFBlackHoleInfoTableLabel :: CLabel Source #

mkRtsPrimOpLabel :: PrimOp -> CLabel Source #

mkRtsSlowFastTickyCtrLabel :: String -> CLabel Source #

mkSelectorInfoLabel :: DynFlags -> Bool -> Int -> CLabel Source #

mkSelectorEntryLabel :: DynFlags -> Bool -> Int -> CLabel Source #

mkCmmInfoLabel :: UnitId -> FastString -> CLabel Source #

mkCmmEntryLabel :: UnitId -> FastString -> CLabel Source #

mkCmmRetInfoLabel :: UnitId -> FastString -> CLabel Source #

mkCmmRetLabel :: UnitId -> FastString -> CLabel Source #

mkCmmCodeLabel :: UnitId -> FastString -> CLabel Source #

mkCmmDataLabel :: UnitId -> NeedExternDecl -> FastString -> CLabel Source #

mkRtsCmmDataLabel :: FastString -> CLabel Source #

mkCmmClosureLabel :: UnitId -> FastString -> CLabel Source #

mkRtsApFastLabel :: FastString -> CLabel Source #

mkPrimCallLabel :: PrimCall -> CLabel Source #

mkForeignLabel :: FastString -> Maybe Int -> ForeignLabelSource -> FunctionOrData -> CLabel Source #

Make a foreign label

addLabelSize :: CLabel -> Int -> CLabel Source #

Update the label size field in a ForeignLabel

foreignLabelStdcallInfo :: CLabel -> Maybe Int Source #

Get the label size field from a ForeignLabel

isBytesLabel :: CLabel -> Bool Source #

Whether label is a top-level string literal

isForeignLabel :: CLabel -> Bool Source #

Whether label is a non-haskell label (defined in C code)

isSomeRODataLabel :: CLabel -> Bool Source #

Whether label is a .rodata label

isStaticClosureLabel :: CLabel -> Bool Source #

Whether label is a static closure label (can come from haskell or cmm)

mkCCLabel :: CostCentre -> CLabel Source #

mkCCSLabel :: CostCentreStack -> CLabel Source #

data DynamicLinkerLabelInfo Source #

Constructors

CodeStub |
SymbolPtr |
GotSymbolPtr |
GotSymbolOffset |

#### Instances

Instances details

Eq DynamicLinkerLabelInfo # |
Instance details Defined in GHC.Cmm.CLabel Methods (==) :: DynamicLinkerLabelInfo -> DynamicLinkerLabelInfo -> Bool # (/=) :: DynamicLinkerLabelInfo -> DynamicLinkerLabelInfo -> Bool #
Ord DynamicLinkerLabelInfo # |
Instance details Defined in GHC.Cmm.CLabel Methods compare :: DynamicLinkerLabelInfo -> DynamicLinkerLabelInfo -> Ordering # (<) :: DynamicLinkerLabelInfo -> DynamicLinkerLabelInfo -> Bool # (<=) :: DynamicLinkerLabelInfo -> DynamicLinkerLabelInfo -> Bool # (>) :: DynamicLinkerLabelInfo -> DynamicLinkerLabelInfo -> Bool # (>=) :: DynamicLinkerLabelInfo -> DynamicLinkerLabelInfo -> Bool # max :: DynamicLinkerLabelInfo -> DynamicLinkerLabelInfo -> DynamicLinkerLabelInfo # min :: DynamicLinkerLabelInfo -> DynamicLinkerLabelInfo -> DynamicLinkerLabelInfo #

mkDynamicLinkerLabel :: DynamicLinkerLabelInfo -> CLabel -> CLabel Source #

dynamicLinkerLabelInfo :: CLabel -> Maybe (DynamicLinkerLabelInfo, CLabel) Source #

mkPicBaseLabel :: CLabel Source #

mkDeadStripPreventer :: CLabel -> CLabel Source #

mkHpcTicksLabel :: Module -> CLabel Source #

# Predicates

hasCAF :: CLabel -> Bool Source #

needsCDecl :: CLabel -> Bool Source #

maybeLocalBlockLabel :: CLabel -> Maybe BlockId Source #

If a label is a local block label then return just its `BlockId`, otherwise `Nothing`.

externallyVisibleCLabel :: CLabel -> Bool Source #

Is a CLabel visible outside this object file or not? From the point of view of the code generator, a name is externally visible if it has to be declared as exported in the .o file's symbol table; that is, made non-static.

isMathFun :: CLabel -> Bool Source #

Check whether a label corresponds to a C function that has a prototype in a system header somewhere, or is built-in to the C compiler. For these labels we avoid generating our own C prototypes.

isCFunctionLabel :: CLabel -> Bool Source #

isGcPtrLabel :: CLabel -> Bool Source #

labelDynamic :: NCGConfig -> Module -> CLabel -> Bool Source #

Does a `CLabel` need dynamic linkage?

When referring to data in code, we need to know whether that data resides in a DLL or not. [Win32 only.] `labelDynamic` returns `True` if the label is located in a DLL, be it a data reference or not.

isLocalCLabel :: Module -> CLabel -> Bool Source #

Is a `CLabel` defined in the current module being compiled?

Sometimes we can optimise references within a compilation unit in ways that we couldn't for inter-module references. This provides a conservative estimate of whether a `CLabel` lives in the current module.

mayRedirectTo :: CLabel -> CLabel -> Bool Source #

# Conversions

toClosureLbl :: CLabel -> CLabel Source #

toSlowEntryLbl :: CLabel -> CLabel Source #

toEntryLbl :: CLabel -> CLabel Source #

toInfoLbl :: CLabel -> CLabel Source #

hasHaskellName :: CLabel -> Maybe Name Source #

pprCLabel :: DynFlags -> CLabel -> SDoc Source #

isInfoTableLabel :: CLabel -> Bool Source #

Whether label is points to some kind of info table

isConInfoTableLabel :: CLabel -> Bool Source #

Whether label is points to constructor info table

isIdLabel :: CLabel -> Bool Source #

isTickyLabel :: CLabel -> Bool Source #