GHC.Runtime.Heap.Layout

Words and bytes

type WordOff = Int Source #

Word offset, or word count

type ByteOff = Int Source #

Byte offset, or byte count

wordsToBytes :: Num a => Platform -> a -> a Source #

Convert the given number of words to a number of bytes.

This function morally has type WordOff -> ByteOff, but uses Num a to allow for overloading.

bytesToWordsRoundUp :: Platform -> ByteOff -> WordOff Source #

First round the given byte count up to a multiple of the machine's word size and then convert the result to words.

roundUpToWords :: Platform -> ByteOff -> ByteOff Source #

Round up the given byte count to the next byte count that's a multiple of the machine's word size.

roundUpTo :: ByteOff -> ByteOff -> ByteOff Source #

Round up base to a multiple of size.

data StgWord Source #

Instances
Instances details
Bits StgWord Source # 
Instance details

Defined in GHC.Runtime.Heap.Layout

Methods

(.&.) :: StgWord -> StgWord -> StgWord Source #

(.|.) :: StgWord -> StgWord -> StgWord Source #

xor :: StgWord -> StgWord -> StgWord Source #

complement :: StgWord -> StgWord Source #

shift :: StgWord -> Int -> StgWord Source #

rotate :: StgWord -> Int -> StgWord Source #

zeroBits :: StgWord Source #

bit :: Int -> StgWord Source #

setBit :: StgWord -> Int -> StgWord Source #

clearBit :: StgWord -> Int -> StgWord Source #

complementBit :: StgWord -> Int -> StgWord Source #

testBit :: StgWord -> Int -> Bool Source #

bitSizeMaybe :: StgWord -> Maybe Int Source #

bitSize :: StgWord -> Int Source #

isSigned :: StgWord -> Bool Source #

shiftL :: StgWord -> Int -> StgWord Source #

unsafeShiftL :: StgWord -> Int -> StgWord Source #

shiftR :: StgWord -> Int -> StgWord Source #

unsafeShiftR :: StgWord -> Int -> StgWord Source #

rotateL :: StgWord -> Int -> StgWord Source #

rotateR :: StgWord -> Int -> StgWord Source #

popCount :: StgWord -> Int Source #

Outputable StgWord Source # 
Instance details

Defined in GHC.Runtime.Heap.Layout

Methods

ppr :: StgWord -> SDoc Source #

Eq StgWord Source # 
Instance details

Defined in GHC.Runtime.Heap.Layout

Methods

(==) :: StgWord -> StgWord -> Bool #

(/=) :: StgWord -> StgWord -> Bool #

fromStgWord :: StgWord -> Integer Source #

toStgWord :: Platform -> Integer -> StgWord Source #

data StgHalfWord Source #

Instances
Instances details
Outputable StgHalfWord Source # 
Instance details

Defined in GHC.Runtime.Heap.Layout

Methods

ppr :: StgHalfWord -> SDoc Source #

Eq StgHalfWord Source # 
Instance details

Defined in GHC.Runtime.Heap.Layout

Methods

(==) :: StgHalfWord -> StgHalfWord -> Bool #

(/=) :: StgHalfWord -> StgHalfWord -> Bool #

fromStgHalfWord :: StgHalfWord -> Integer Source #

toStgHalfWord :: Platform -> Integer -> StgHalfWord Source #

halfWordSize :: Platform -> ByteOff Source #

Half word size in bytes

halfWordSizeInBits :: Platform -> Int Source #

Closure representation

data SMRep Source #

A description of the layout of a closure. Corresponds directly to the closure types in includes/rts/storage/ClosureTypes.h.

Constructors

HeapRep IsStatic !WordOff !WordOff ClosureTypeInfo 
ArrayPtrsRep !WordOff !WordOff 
SmallArrayPtrsRep !WordOff 
ArrayWordsRep !WordOff 
StackRep Liveness 
RTSRep Int SMRep 
Instances
Instances details
Outputable SMRep Source # 
Instance details

Defined in GHC.Runtime.Heap.Layout

Methods

ppr :: SMRep -> SDoc Source #

Eq SMRep Source # 
Instance details

Defined in GHC.Runtime.Heap.Layout

Methods

(==) :: SMRep -> SMRep -> Bool #

(/=) :: SMRep -> SMRep -> Bool #

type IsStatic = Bool Source #

True <=> This is a static closure. Affects how we garbage-collect it. Static closure have an extra static link field at the end. Constructors do not have a static variant; see Note [static constructors]

data ClosureTypeInfo Source #

Constructors

Constr ConTagZ ConstrDescription 
Fun FunArity ArgDescr 
Thunk 
ThunkSelector SelectorOffset 
BlackHole 
IndStatic 
Instances
Instances details
Outputable ClosureTypeInfo Source # 
Instance details

Defined in GHC.Runtime.Heap.Layout

Methods

ppr :: ClosureTypeInfo -> SDoc Source #

Eq ClosureTypeInfo Source # 
Instance details

Defined in GHC.Runtime.Heap.Layout

Methods

(==) :: ClosureTypeInfo -> ClosureTypeInfo -> Bool #

(/=) :: ClosureTypeInfo -> ClosureTypeInfo -> Bool #

data ArgDescr Source #

An ArgDescr describes the argument pattern of a function

Constructors

ArgSpec !Int 
ArgGen Liveness 
ArgUnknown 
Instances
Instances details
Outputable ArgDescr Source # 
Instance details

Defined in GHC.Runtime.Heap.Layout

Methods

ppr :: ArgDescr -> SDoc Source #

Eq ArgDescr Source # 
Instance details

Defined in GHC.Runtime.Heap.Layout

Methods

(==) :: ArgDescr -> ArgDescr -> Bool #

(/=) :: ArgDescr -> ArgDescr -> Bool #

type Liveness = [Bool] Source #

We represent liveness bitmaps as a Bitmap (whose internal representation really is a bitmap). These are pinned onto case return vectors to indicate the state of the stack for the garbage collector.

In the compiled program, liveness bitmaps that fit inside a single word (StgWord) are stored as a single word, while larger bitmaps are stored as a pointer to an array of words.

type ConstrDescription = ByteString Source #

Construction

mkHeapRep :: Profile -> IsStatic -> WordOff -> WordOff -> ClosureTypeInfo -> SMRep Source #

blackHoleRep :: SMRep Source #

indStaticRep :: SMRep Source #

mkStackRep :: [Bool] -> SMRep Source #

mkRTSRep :: Int -> SMRep -> SMRep Source #

arrPtrsRep :: Platform -> WordOff -> SMRep Source #

smallArrPtrsRep :: WordOff -> SMRep Source #

arrWordsRep :: Platform -> ByteOff -> SMRep Source #

Predicates

isStaticRep :: SMRep -> IsStatic Source #

isConRep :: SMRep -> Bool Source #

isThunkRep :: SMRep -> Bool Source #

isFunRep :: SMRep -> Bool Source #

isStaticNoCafCon :: SMRep -> Bool Source #

isStackRep :: SMRep -> Bool Source #

Size-related things

heapClosureSizeW :: Profile -> SMRep -> WordOff Source #

The total size of the closure, in words.

fixedHdrSizeW :: Profile -> WordOff Source #

Size of a closure header (StgHeader in includes/rts/storage/Closures.h)

arrWordsHdrSize :: Profile -> ByteOff Source #

arrWordsHdrSizeW :: Profile -> WordOff Source #

arrPtrsHdrSize :: Profile -> ByteOff Source #

arrPtrsHdrSizeW :: Profile -> WordOff Source #

profHdrSize :: Profile -> WordOff Source #

Size of the profiling part of a closure header (StgProfHeader in includes/rts/storage/Closures.h)

thunkHdrSize :: Profile -> WordOff Source #

nonHdrSize :: Platform -> SMRep -> ByteOff Source #

nonHdrSizeW :: SMRep -> WordOff Source #

smallArrPtrsHdrSize :: Profile -> ByteOff Source #

smallArrPtrsHdrSizeW :: Profile -> WordOff Source #

hdrSize :: Profile -> SMRep -> ByteOff Source #

hdrSizeW :: Profile -> SMRep -> WordOff Source #

fixedHdrSize :: Profile -> ByteOff Source #

RTS closure types

rtsClosureType :: SMRep -> Int Source #

Derives the RTS closure type from an SMRep

rET_SMALL :: Int Source #

rET_BIG :: Int Source #

aRG_GEN :: Int Source #

aRG_GEN_BIG :: Int Source #

Arrays

card :: Platform -> Int -> Int Source #

The byte offset into the card table of the card for a given element

cardRoundUp :: Platform -> Int -> Int Source #

Convert a number of elements to a number of cards, rounding up

cardTableSizeB :: Platform -> Int -> ByteOff Source #

The size of a card table, in bytes

cardTableSizeW :: Platform -> Int -> WordOff Source #

The size of a card table, in words