GHC.CmmToAsm.Wasm.Types

Documentation

data WasmType

WebAssembly type of a WebAssembly value that WebAssembly code could either expect on the evaluation stack or leave on the evaluation stack.

Constructors

I32

I64

F32

F64

Instances

TestEquality WasmTypeTag

Defined in GHC.CmmToAsm.Wasm.Types

Methods

testEquality :: forall (a :: k) (b :: k). WasmTypeTag a -> WasmTypeTag b -> Maybe (a :~: b)

data WasmTypeTag :: WasmType -> Type where

Singleton type useful for programming with WasmType at the type level.

Constructors

TagI32 :: WasmTypeTag 'I32

TagI64 :: WasmTypeTag 'I64

TagF32 :: WasmTypeTag 'F32

TagF64 :: WasmTypeTag 'F64

Instances

TestEquality WasmTypeTag

Defined in GHC.CmmToAsm.Wasm.Types

Methods

testEquality :: forall (a :: k) (b :: k). WasmTypeTag a -> WasmTypeTag b -> Maybe (a :~: b)

Show (WasmTypeTag t)

Defined in GHC.CmmToAsm.Wasm.Types

Methods

showsPrec :: Int -> WasmTypeTag t -> ShowS

show :: WasmTypeTag t -> String

showList :: [WasmTypeTag t] -> ShowS

data SomeWasmType where

Constructors

SomeWasmType :: WasmTypeTag t -> SomeWasmType

Instances

Eq SomeWasmType

Defined in GHC.CmmToAsm.Wasm.Types

Methods

(==) :: SomeWasmType -> SomeWasmType -> Bool

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

data TypeList :: [WasmType] -> Type where

List of WebAssembly types used to describe the sequence of WebAssembly values that a block of code may expect on the stack or leave on the stack.

Constructors

TypeListNil :: TypeList '[]

TypeListCons :: WasmTypeTag t -> TypeList ts -> TypeList (t : ts)

someWasmTypesFromTypeList :: TypeList ts -> [SomeWasmType]

data WasmFunctionType pre post

The type of a WebAssembly function, loop, block, or conditional. This type says what values the code expects to pop off the stack and what values it promises to push. The WebAssembly standard requires that this type appear explicitly in the code.

Constructors

WasmFunctionType

Fields

• ft_pops :: TypeList pre
• ft_pushes :: TypeList post

newtype SymName

For simplicity, we record other metadata in WasmCodeGenState by need, instead of carrying them along with SymName.

Constructors

SymName FastString

Instances

IsString SymName

Defined in GHC.CmmToAsm.Wasm.Types

Methods

fromString :: String -> SymName

Show SymName

Defined in GHC.CmmToAsm.Wasm.Types

Methods

showsPrec :: Int -> SymName -> ShowS

show :: SymName -> String

showList :: [SymName] -> ShowS

Uniquable SymName

Defined in GHC.CmmToAsm.Wasm.Types

Methods

getUnique :: SymName -> Unique

Eq SymName

Defined in GHC.CmmToAsm.Wasm.Types

Methods

(==) :: SymName -> SymName -> Bool

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

Ord SymName

Defined in GHC.CmmToAsm.Wasm.Types

Methods

compare :: SymName -> SymName -> Ordering

(<) :: SymName -> SymName -> Bool

(<=) :: SymName -> SymName -> Bool

(>) :: SymName -> SymName -> Bool

(>=) :: SymName -> SymName -> Bool

max :: SymName -> SymName -> SymName

min :: SymName -> SymName -> SymName

data SymVisibility

Constructors

SymUndefined

Not defined in the current compilation unit.

[ undefined binding=global vis=default ]

SymStatic

Defined, not visible to other compilation units.

[ binding=local vis=default ]

SymDefault

Defined, visible to other compilation units.

Adds .hidden & .globl directives in the output assembly.

[ binding=global vis=hidden ]

data SymKind

Represents whether a symbol is a data symbol or a function symbol. Unlike linkers for other targets, wasm-ld does panic at link-time if it finds symbol kind inconsistency between the definition site and other use sites.

Currently we solely rely on isCFunctionLabel to determine a symbol's kind, but it does take extra effort to make it work. The main source of inconsistency arises from hand-written Cmm sources, where it's possible to refer to external entities like xxx_info and xxx_closure without explicit import CLOSURE declarations. The Cmm parser will implicitly assume those are foreign function labels, and then this will break the WebAssembly backend. #22368 provides more context on this issue.

tl;dr for any GHC contributor that accidentally triggers wasm-ld errors when hacking Cmm: whatever data symbols are used in new code, just add the corresponding import CLOSURE declarations at the top of that Cmm file.

Constructors

SymData

SymFunc

Instances

Eq SymKind

Defined in GHC.CmmToAsm.Wasm.Types

Methods

(==) :: SymKind -> SymKind -> Bool

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

data DataSectionKind

WebAssembly doesn't really have proper read-only memory regions yet. Neverthless we add the .rodata logic here, wasm-ld will aggregate all .rodata sections into a single one, which adds possibility for runtime checks later, either via a customized runtime, or via code instrumentation. See https://github.com/llvm/llvm-project/blob/b296aed8ae239c20ebdd7969e978f8d2a3b9c178/lld/wasm/Writer.cpp#L856

Constructors

SectionData

SectionROData

data DataSectionContent

Neither Cmm or Wasm type system takes integer signedness into account, therefore we always round up a CmmExpr to the right width and handle it as an untyped integer.

Constructors

DataI8 Word8

DataI16 Word16

DataI32 Word32

DataI64 Word64

DataF32 Float

DataF64 Double

DataSym SymName Int

DataSkip Int

DataASCII ByteString

DataIncBin FilePath Int

data DataSection

Constructors

DataSection

Fields

• dataSectionKind :: DataSectionKind
• dataSectionAlignment :: Alignment
• dataSectionContents :: [DataSectionContent]

type GlobalInfo = (SymName, SomeWasmType)

type LocalInfo = (Int, SomeWasmType)

data FuncBody w

Constructors

FuncBody

Fields

• funcLocals :: [SomeWasmType]
• funcBody :: WasmControl (WasmStatements w) (WasmExpr w w) '[] '[w]

  Most are Cmm functions, but may also contain synthesized function of other types, sigh.

data Signage

Constructors

Signed

Unsigned

data WasmInstr :: WasmType -> [WasmType] -> [WasmType] -> Type where

The w type variable in the Wasm IR stands for "platform word type", so TagI32 on wasm32, and TagI64 on wasm64. This way, we can make the codegen logic work on both wasm32/wasm64 in a type-safe manner.

Constructors

WasmComment :: String -> WasmInstr w pre pre

WasmNop :: WasmInstr w pre pre

WasmDrop :: WasmInstr w (t : pre) pre

WasmUnreachable :: WasmInstr w pre post

WasmConst :: WasmTypeTag t -> Integer -> WasmInstr w pre (t : pre)

WasmSymConst :: SymName -> WasmInstr w pre (w : pre)

WasmLoad :: WasmTypeTag t -> Maybe Int -> Signage -> Int -> AlignmentSpec -> WasmInstr w (w : pre) (t : pre)

WasmStore :: WasmTypeTag t -> Maybe Int -> Int -> AlignmentSpec -> WasmInstr w (t : (w : pre)) pre

WasmGlobalGet :: WasmTypeTag t -> SymName -> WasmInstr w pre (t : pre)

WasmGlobalSet :: WasmTypeTag t -> SymName -> WasmInstr w (t : pre) pre

WasmLocalGet :: WasmTypeTag t -> Int -> WasmInstr w pre (t : pre)

WasmLocalSet :: WasmTypeTag t -> Int -> WasmInstr w (t : pre) pre

WasmLocalTee :: WasmTypeTag t -> Int -> WasmInstr w (t : pre) (t : pre)

WasmCCall :: SymName -> WasmInstr w pre post

WasmCCallIndirect :: TypeList arg_tys -> TypeList ret_tys -> WasmInstr w (w : pre) post

WasmConcat :: WasmInstr w pre mid -> WasmInstr w mid post -> WasmInstr w pre post

WasmReinterpret :: WasmTypeTag t0 -> WasmTypeTag t1 -> WasmInstr w (t0 : pre) (t1 : pre)

WasmTruncSat :: Signage -> WasmTypeTag t0 -> WasmTypeTag t1 -> WasmInstr w (t0 : pre) (t1 : pre)

WasmConvert :: Signage -> WasmTypeTag t0 -> WasmTypeTag t1 -> WasmInstr w (t0 : pre) (t1 : pre)

WasmAdd :: WasmTypeTag t -> WasmInstr w (t : (t : pre)) (t : pre)

WasmSub :: WasmTypeTag t -> WasmInstr w (t : (t : pre)) (t : pre)

WasmMul :: WasmTypeTag t -> WasmInstr w (t : (t : pre)) (t : pre)

WasmDiv :: Signage -> WasmTypeTag t -> WasmInstr w (t : (t : pre)) (t : pre)

WasmRem :: Signage -> WasmTypeTag t -> WasmInstr w (t : (t : pre)) (t : pre)

WasmAnd :: WasmTypeTag t -> WasmInstr w (t : (t : pre)) (t : pre)

WasmOr :: WasmTypeTag t -> WasmInstr w (t : (t : pre)) (t : pre)

WasmXor :: WasmTypeTag t -> WasmInstr w (t : (t : pre)) (t : pre)

WasmEq :: WasmTypeTag t -> WasmInstr w (t : (t : pre)) (w : pre)

WasmNe :: WasmTypeTag t -> WasmInstr w (t : (t : pre)) (w : pre)

WasmLt :: Signage -> WasmTypeTag t -> WasmInstr w (t : (t : pre)) (w : pre)

WasmGt :: Signage -> WasmTypeTag t -> WasmInstr w (t : (t : pre)) (w : pre)

WasmLe :: Signage -> WasmTypeTag t -> WasmInstr w (t : (t : pre)) (w : pre)

WasmGe :: Signage -> WasmTypeTag t -> WasmInstr w (t : (t : pre)) (w : pre)

WasmShl :: WasmTypeTag t -> WasmInstr w (t : (t : pre)) (t : pre)

WasmShr :: Signage -> WasmTypeTag t -> WasmInstr w (t : (t : pre)) (t : pre)

WasmI32Extend8S :: WasmInstr w ('I32 : pre) ('I32 : pre)

WasmI32Extend16S :: WasmInstr w ('I32 : pre) ('I32 : pre)

WasmI64Extend8S :: WasmInstr w ('I64 : pre) ('I64 : pre)

WasmI64Extend16S :: WasmInstr w ('I64 : pre) ('I64 : pre)

WasmI64Extend32S :: WasmInstr w ('I64 : pre) ('I64 : pre)

WasmI64ExtendI32 :: Signage -> WasmInstr w ('I32 : pre) ('I64 : pre)

WasmI32WrapI64 :: WasmInstr w ('I64 : pre) ('I32 : pre)

WasmF32DemoteF64 :: WasmInstr w ('F64 : pre) ('F32 : pre)

WasmF64PromoteF32 :: WasmInstr w ('F32 : pre) ('F64 : pre)

WasmAbs :: WasmTypeTag t -> WasmInstr w (t : pre) (t : pre)

WasmNeg :: WasmTypeTag t -> WasmInstr w (t : pre) (t : pre)

WasmCond :: WasmInstr w pre pre -> WasmInstr w (w : pre) pre

newtype WasmExpr w t

Constructors

WasmExpr (forall pre. WasmInstr w pre (t : pre))

data SomeWasmExpr w where

Constructors

SomeWasmExpr :: WasmTypeTag t -> WasmExpr w t -> SomeWasmExpr w

newtype WasmStatements w

Constructors

WasmStatements (forall pre. WasmInstr w pre pre)

data WasmControl :: Type -> Type -> [WasmType] -> [WasmType] -> Type where

Representation of WebAssembly control flow. Normally written as WasmControl s e pre post Type parameter s is the type of (unspecified) statements. It might be instantiated with an open Cmm block or with a sequence of Wasm instructions. Parameter e is the type of expressions. Parameter pre represents the values that are expected on the WebAssembly stack when the code runs, and post represents the state of the stack on completion.

Constructors

WasmPush :: WasmTypeTag t -> e -> WasmControl s e stack (t : stack)

WasmBlock :: WasmFunctionType pre post -> WasmControl s e pre post -> WasmControl s e pre post

WasmLoop :: WasmFunctionType pre post -> WasmControl s e pre post -> WasmControl s e pre post

WasmIfTop :: WasmFunctionType pre post -> WasmControl s e pre post -> WasmControl s e pre post -> WasmControl s e ('I32 : pre) post

WasmBr :: Int -> WasmControl s e dropped destination

WasmFallthrough :: WasmControl s e dropped destination

WasmBrTable :: e -> BrTableInterval -> [Int] -> Int -> WasmControl s e dropped destination

WasmTailCall :: e -> WasmControl s e t1star t2star

WasmActions :: s -> WasmControl s e stack stack

WasmSeq :: WasmControl s e pre mid -> WasmControl s e mid post -> WasmControl s e pre post

data BrTableInterval

Constructors

BrTableInterval

Fields

• bti_lo :: Integer
• bti_count :: Integer

Instances

Show BrTableInterval

Defined in GHC.CmmToAsm.Wasm.Types

Methods

showsPrec :: Int -> BrTableInterval -> ShowS

show :: BrTableInterval -> String

showList :: [BrTableInterval] -> ShowS

Outputable BrTableInterval

Defined in GHC.CmmToAsm.Wasm.Types

Methods

ppr :: BrTableInterval -> SDoc

wasmControlCast :: WasmControl s e pre post -> WasmControl s e pre' post'

data WasmCodeGenState w

Constructors

WasmCodeGenState

Fields

• wasmPlatform :: Platform

  Target platform

• defaultSyms :: SymSet

  Defined symbols with SymDefault visibility.

• funcTypes :: SymMap ([SomeWasmType], [SomeWasmType])

  Function types, defined or not. There may exist a function whose type is unknown (e.g. as a function pointer), in that case we fall back to () -> (), it's imperfect but works with wasm-ld.

• funcBodies :: SymMap (FuncBody w)

  Defined function bodies.

• dataSections :: SymMap DataSection

  Defined data sections.

• ctors :: [SymName]

  ctors in the current compilation unit.

• localRegs :: UniqFM LocalReg LocalInfo
• localRegsCount :: Int
• wasmUniqSupply :: UniqSupply

initialWasmCodeGenState :: Platform -> UniqSupply -> WasmCodeGenState w

newtype WasmCodeGenM w a

Constructors

WasmCodeGenM (State (WasmCodeGenState w) a)

Instances

Applicative (WasmCodeGenM w)

Defined in GHC.CmmToAsm.Wasm.Types

Methods

pure :: a -> WasmCodeGenM w a

(<*>) :: WasmCodeGenM w (a -> b) -> WasmCodeGenM w a -> WasmCodeGenM w b

liftA2 :: (a -> b -> c) -> WasmCodeGenM w a -> WasmCodeGenM w b -> WasmCodeGenM w c

(*>) :: WasmCodeGenM w a -> WasmCodeGenM w b -> WasmCodeGenM w b

(<*) :: WasmCodeGenM w a -> WasmCodeGenM w b -> WasmCodeGenM w a

Functor (WasmCodeGenM w)

Defined in GHC.CmmToAsm.Wasm.Types

Methods

fmap :: (a -> b) -> WasmCodeGenM w a -> WasmCodeGenM w b

(<$) :: a -> WasmCodeGenM w b -> WasmCodeGenM w a

Monad (WasmCodeGenM w)

Defined in GHC.CmmToAsm.Wasm.Types

Methods

(>>=) :: WasmCodeGenM w a -> (a -> WasmCodeGenM w b) -> WasmCodeGenM w b

(>>) :: WasmCodeGenM w a -> WasmCodeGenM w b -> WasmCodeGenM w b

return :: a -> WasmCodeGenM w a

wasmGetsM :: (WasmCodeGenState w -> a) -> WasmCodeGenM w a

wasmPlatformM :: WasmCodeGenM w Platform

wasmWordTypeM :: WasmCodeGenM w (WasmTypeTag w)

wasmWordCmmTypeM :: WasmCodeGenM w CmmType

wasmStateM :: (WasmCodeGenState w -> (# a, WasmCodeGenState w #)) -> WasmCodeGenM w a

wasmModifyM :: (WasmCodeGenState w -> WasmCodeGenState w) -> WasmCodeGenM w ()

wasmExecM :: WasmCodeGenM w a -> WasmCodeGenState w -> WasmCodeGenState w

wasmUniq :: WasmCodeGenM w Unique