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-rw-r--r--libraries/ghc-bignum/src/GHC/Num/BigNat.hs1509
-rw-r--r--libraries/ghc-bignum/src/GHC/Num/BigNat.hs-boot19
-rw-r--r--libraries/ghc-bignum/src/GHC/Num/BigNat/Check.hs456
-rw-r--r--libraries/ghc-bignum/src/GHC/Num/BigNat/FFI.hs581
-rw-r--r--libraries/ghc-bignum/src/GHC/Num/BigNat/GMP.hs498
-rw-r--r--libraries/ghc-bignum/src/GHC/Num/BigNat/Native.hs719
-rw-r--r--libraries/ghc-bignum/src/GHC/Num/Integer.hs1169
-rw-r--r--libraries/ghc-bignum/src/GHC/Num/Natural.hs557
-rw-r--r--libraries/ghc-bignum/src/GHC/Num/Natural.hs-boot23
-rw-r--r--libraries/ghc-bignum/src/GHC/Num/Primitives.hs623
-rw-r--r--libraries/ghc-bignum/src/GHC/Num/WordArray.hs432
11 files changed, 6586 insertions, 0 deletions
diff --git a/libraries/ghc-bignum/src/GHC/Num/BigNat.hs b/libraries/ghc-bignum/src/GHC/Num/BigNat.hs
new file mode 100644
index 0000000000..5d0a9919f5
--- /dev/null
+++ b/libraries/ghc-bignum/src/GHC/Num/BigNat.hs
@@ -0,0 +1,1509 @@
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE MultiWayIf #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE PolyKinds #-}
+{-# LANGUAGE KindSignatures #-}
+{-# LANGUAGE BinaryLiterals #-}
+{-# OPTIONS_GHC -Wno-name-shadowing #-}
+
+-- | Multi-precision natural
+module GHC.Num.BigNat where
+
+#include "MachDeps.h"
+#include "WordSize.h"
+
+import GHC.Prim
+import GHC.Types
+import GHC.Classes
+import GHC.Magic
+import GHC.Num.Primitives
+import GHC.Num.WordArray
+
+#if WORD_SIZE_IN_BITS < 64
+import GHC.IntWord64
+#endif
+
+#if defined(BIGNUM_CHECK)
+import GHC.Num.BigNat.Check
+
+#elif defined(BIGNUM_NATIVE)
+import GHC.Num.BigNat.Native
+
+#elif defined(BIGNUM_FFI)
+import GHC.Num.BigNat.FFI
+
+#elif defined(BIGNUM_GMP)
+import GHC.Num.BigNat.GMP
+
+#else
+#error Undefined BigNat backend. Use a flag to select it (e.g. gmp, native, ffi)`
+#endif
+
+default ()
+
+-- | A BigNat
+--
+-- Represented as an array of limbs (Word#) stored in little-endian order (Word#
+-- themselves use machine order).
+--
+-- Invariant (canonical representation): higher Word# is non-zero.
+-- As a consequence, zero is represented with a WordArray# whose size is 0.
+type BigNat = WordArray# -- we use a type-alias to make Integer/Natural easier to wire-in
+
+-- | Check that the BigNat is valid
+bigNatCheck# :: BigNat -> Bool#
+bigNatCheck# bn
+ | 0# <- bigNatSize# bn = 1#
+ | 0## <- bigNatIndex# bn (bigNatSize# bn -# 1#) = 0#
+ | True = 1#
+
+-- | Check that the BigNat is valid
+bigNatCheck :: BigNat -> Bool
+bigNatCheck bn = isTrue# (bigNatCheck# bn)
+
+-- | Number of words in the BigNat
+bigNatSize :: BigNat -> Word
+bigNatSize bn = W# (int2Word# (bigNatSize# bn))
+
+-- | Number of words in the BigNat
+bigNatSize# :: BigNat -> Int#
+bigNatSize# ba = wordArraySize# ba
+
+-- Note [Why Void#?]
+-- ~~~~~~~~~~~~~~~~~
+--
+-- We can't have top-level BigNat for now because they are unlifted ByteArray#
+-- (see #17521). So we use functions that take an empty argument Void# that
+-- will be discarded at compile time.
+
+data BigNatW = BigNatW BigNat
+
+{-# NOINLINE bigNatZeroW #-}
+bigNatZeroW :: BigNatW
+bigNatZeroW = BigNatW (withNewWordArray# 0# (\_ s -> s))
+
+{-# NOINLINE bigNatOneW #-}
+bigNatOneW :: BigNatW
+bigNatOneW = BigNatW (bigNatFromWord# 1##)
+
+-- | BigNat Zero
+bigNatZero :: Void# -> BigNat -- cf Note [Why Void#?]
+bigNatZero _ = case bigNatZeroW of
+ BigNatW w -> w
+
+-- | BigNat one
+bigNatOne :: Void# -> BigNat -- cf Note [Why Void#?]
+bigNatOne _ = case bigNatOneW of
+ BigNatW w -> w
+
+-- | Indicate if a bigNat is zero
+bigNatIsZero :: BigNat -> Bool
+bigNatIsZero bn = isTrue# (bigNatIsZero# bn)
+
+-- | Indicate if a bigNat is zero
+bigNatIsZero# :: BigNat -> Bool#
+bigNatIsZero# ba = wordArraySize# ba ==# 0#
+
+-- | Indicate if a bigNat is one
+bigNatIsOne :: BigNat -> Bool
+bigNatIsOne bn = isTrue# (bigNatIsOne# bn)
+
+-- | Indicate if a bigNat is one
+bigNatIsOne# :: BigNat -> Bool#
+bigNatIsOne# ba =
+ wordArraySize# ba ==# 1#
+ &&# indexWordArray# ba 0# `eqWord#` 1##
+
+-- | Indicate if a bigNat is two
+bigNatIsTwo :: BigNat -> Bool
+bigNatIsTwo bn = isTrue# (bigNatIsTwo# bn)
+
+-- | Indicate if a bigNat is two
+bigNatIsTwo# :: BigNat -> Bool#
+bigNatIsTwo# ba =
+ wordArraySize# ba ==# 1#
+ &&# indexWordArray# ba 0# `eqWord#` 2##
+
+-- | Indicate if the value is a power of two and which one
+bigNatIsPowerOf2# :: BigNat -> (# () | Word# #)
+bigNatIsPowerOf2# a
+ | bigNatIsZero a = (# () | #)
+ | True = case wordIsPowerOf2# msw of
+ (# () | #) -> (# () | #)
+ (# | c #) -> case checkAllZeroes (imax -# 1#) of
+ 0# -> (# () | #)
+ _ -> (# | c `plusWord#`
+ (int2Word# imax `uncheckedShiftL#` WORD_SIZE_BITS_SHIFT#) #)
+ where
+ msw = bigNatIndex# a imax
+ sz = bigNatSize# a
+ imax = sz -# 1#
+ checkAllZeroes i
+ | isTrue# (i <# 0#) = 1#
+ | True = case bigNatIndex# a i of
+ 0## -> checkAllZeroes (i -# 1#)
+ _ -> 0#
+
+-- | Return the Word# at the given index
+bigNatIndex# :: BigNat -> Int# -> Word#
+bigNatIndex# x i = indexWordArray# x i
+
+-- | Return the Word# at the given index
+bigNatIndex :: BigNat -> Int# -> Word
+bigNatIndex bn i = W# (bigNatIndex# bn i)
+
+-------------------------------------------------
+-- Conversion
+-------------------------------------------------
+
+-- | Create a BigNat from a Word
+bigNatFromWord :: Word -> BigNat
+bigNatFromWord (W# w) = bigNatFromWord# w
+
+-- | Create a BigNat from a Word
+bigNatFromWord# :: Word# -> BigNat
+bigNatFromWord# 0## = bigNatZero void#
+bigNatFromWord# w = wordArrayFromWord# w
+
+-- | Convert a list of non-zero Words (most-significant first) into a BigNat
+bigNatFromWordList :: [Word] -> BigNat
+bigNatFromWordList (W# 0##:xs) = bigNatFromWordList xs
+bigNatFromWordList xs = bigNatFromWordListUnsafe xs
+
+-- | Convert a list of non-zero Words (most-significant first) into a BigNat
+bigNatFromWordList# :: [Word] -> WordArray#
+{-# NOINLINE bigNatFromWordList# #-}
+bigNatFromWordList# xs = bigNatFromWordList xs
+
+-- | Return the absolute value of the Int# in a BigNat
+bigNatFromAbsInt# :: Int# -> BigNat
+bigNatFromAbsInt# i = bigNatFromWord# (wordFromAbsInt# i)
+
+-- | Convert a list of non-zero Words (most-significant first) into a BigNat.
+-- Don't remove most-significant zero words
+bigNatFromWordListUnsafe :: [Word] -> BigNat
+bigNatFromWordListUnsafe [] = bigNatZero void#
+bigNatFromWordListUnsafe xs =
+ let
+ length i [] = i
+ length i (_:ys) = length (i +# 1#) ys
+ !lxs = length 0# xs
+ writeWordList _mwa _i [] s = s
+ writeWordList mwa i (W# w:ws) s =
+ case mwaWrite# mwa i w s of
+ s1 -> writeWordList mwa (i -# 1#) ws s1
+ in withNewWordArray# lxs \mwa ->
+ writeWordList mwa (lxs -# 1#) xs
+
+-- | Convert a BigNat into a list of non-zero Words (most-significant first)
+bigNatToWordList :: BigNat -> [Word]
+bigNatToWordList bn = go (bigNatSize# bn)
+ where
+ go 0# = []
+ go n = bigNatIndex bn (n -# 1#) : go (n -# 1#)
+
+
+-- | Convert two Word# (most-significant first) into a BigNat
+bigNatFromWord2# :: Word# -> Word# -> BigNat
+bigNatFromWord2# 0## 0## = bigNatZero void#
+bigNatFromWord2# 0## n = bigNatFromWord# n
+bigNatFromWord2# w1 w2 = wordArrayFromWord2# w1 w2
+
+-- | Convert a BigNat into a Word#
+bigNatToWord# :: BigNat -> Word#
+bigNatToWord# a
+ | bigNatIsZero a = 0##
+ | True = bigNatIndex# a 0#
+
+-- | Convert a BigNat into a Word# if it fits
+bigNatToWordMaybe# :: BigNat -> (# Word# | () #)
+bigNatToWordMaybe# a
+ | bigNatIsZero a = (# 0## | #)
+ | isTrue# (bigNatSize# a ># 1#) = (# | () #)
+ | True = (# bigNatIndex# a 0# | #)
+
+-- | Convert a BigNat into a Word
+bigNatToWord :: BigNat -> Word
+bigNatToWord bn = W# (bigNatToWord# bn)
+
+-- | Convert a BigNat into a Int#
+bigNatToInt# :: BigNat -> Int#
+bigNatToInt# a
+ | bigNatIsZero a = 0#
+ | True = indexIntArray# a 0#
+
+-- | Convert a BigNat into a Int
+bigNatToInt :: BigNat -> Int
+bigNatToInt bn = I# (bigNatToInt# bn)
+
+#if WORD_SIZE_IN_BITS == 32
+
+-- | Convert a Word64# into a BigNat on 32-bit architectures
+bigNatFromWord64# :: Word64# -> BigNat
+bigNatFromWord64# w64 = bigNatFromWord2# wh# wl#
+ where
+ wh# = word64ToWord# (uncheckedShiftRL64# w64 32#)
+ wl# = word64ToWord# w64
+
+-- | Convert a BigNat into a Word64# on 32-bit architectures
+bigNatToWord64# :: BigNat -> Word64#
+bigNatToWord64# b
+ | bigNatIsZero b = wordToWord64# 0##
+ | wl <- wordToWord64# (bigNatToWord# b)
+ = if isTrue# (bigNatSize# b ># 1#)
+ then
+ let wh = wordToWord64# (bigNatIndex# b 1#)
+ in uncheckedShiftL64# wh 32# `or64#` wl
+ else wl
+
+#endif
+
+-- | Encode (# BigNat mantissa, Int# exponent #) into a Double#
+bigNatEncodeDouble# :: BigNat -> Int# -> Double#
+bigNatEncodeDouble# a e
+ | bigNatIsZero a
+ = word2Double# 0## -- FIXME: isn't it NaN on 0# exponent?
+
+ | True
+ = inline bignat_encode_double a e
+
+-------------------------------------------------
+-- Predicates
+-------------------------------------------------
+
+-- | Test if a BigNat is greater than a Word
+bigNatGtWord# :: BigNat -> Word# -> Bool#
+bigNatGtWord# bn w =
+ notB# (bigNatIsZero# bn)
+ &&# ( bigNatSize# bn ># 1#
+ ||# bigNatIndex# bn 0# `gtWord#` w
+ )
+
+-- | Test if a BigNat is equal to a Word
+bigNatEqWord# :: BigNat -> Word# -> Bool#
+bigNatEqWord# bn w
+ | 0## <- w
+ = bigNatIsZero# bn
+
+ | isTrue# (bigNatSize# bn ==# 1#)
+ = bigNatIndex# bn 0# `eqWord#` w
+
+ | True
+ = 0#
+
+-- | Test if a BigNat is greater than a Word
+bigNatGtWord :: BigNat -> Word -> Bool
+bigNatGtWord bn (W# w) = isTrue# (bigNatGtWord# bn w)
+
+-- | Test if a BigNat is lower than or equal to a Word
+bigNatLeWord# :: BigNat -> Word# -> Bool#
+bigNatLeWord# bn w = notB# (bigNatGtWord# bn w)
+
+-- | Test if a BigNat is lower than or equal to a Word
+bigNatLeWord :: BigNat -> Word -> Bool
+bigNatLeWord bn (W# w) = isTrue# (bigNatLeWord# bn w)
+
+-- | Equality test for BigNat
+bigNatEq# :: BigNat -> BigNat -> Bool#
+bigNatEq# wa wb
+ | isTrue# (wordArraySize# wa /=# wordArraySize# wb) = 0#
+ | isTrue# (wordArraySize# wa ==# 0#) = 1#
+ | True = inline bignat_compare wa wb ==# 0#
+
+-- | Equality test for BigNat
+bigNatEq :: BigNat -> BigNat -> Bool
+bigNatEq a b = isTrue# (bigNatEq# a b)
+
+-- | Inequality test for BigNat
+bigNatNe# :: BigNat -> BigNat -> Bool#
+bigNatNe# a b = notB# (bigNatEq# a b)
+
+-- | Equality test for BigNat
+bigNatNe :: BigNat -> BigNat -> Bool
+bigNatNe a b = isTrue# (bigNatNe# a b)
+
+-- | Compare a BigNat and a Word#
+bigNatCompareWord# :: BigNat -> Word# -> Ordering
+bigNatCompareWord# a b
+ | bigNatIsZero a = cmpW# 0## b
+ | isTrue# (wordArraySize# a ># 1#) = GT
+ | True
+ = cmpW# (indexWordArray# a 1#) b
+
+-- | Compare a BigNat and a Word
+bigNatCompareWord :: BigNat -> Word -> Ordering
+bigNatCompareWord a (W# b) = bigNatCompareWord# a b
+
+-- | Compare two BigNat
+bigNatCompare :: BigNat -> BigNat -> Ordering
+bigNatCompare a b =
+ let
+ szA = wordArraySize# a
+ szB = wordArraySize# b
+ in if
+ | isTrue# (szA ># szB) -> GT
+ | isTrue# (szA <# szB) -> LT
+ | isTrue# (szA ==# 0#) -> EQ
+ | True -> compareInt# (inline bignat_compare a b) 0#
+
+
+-- | Predicate: a < b
+bigNatLt :: BigNat -> BigNat -> Bool
+bigNatLt a b = bigNatCompare a b == LT
+
+-------------------------------------------------
+-- Addition
+-------------------------------------------------
+
+-- | Add a bigNat and a Word#
+bigNatAddWord# :: BigNat -> Word# -> BigNat
+bigNatAddWord# a b
+ | 0## <- b
+ = a
+
+ | bigNatIsZero a
+ = bigNatFromWord# b
+
+ | True
+ = withNewWordArrayTrimed# (wordArraySize# a +# 1#) \mwa s ->
+ inline bignat_add_word mwa a b s
+
+-- | Add a bigNat and a Word
+bigNatAddWord :: BigNat -> Word -> BigNat
+bigNatAddWord a (W# b) = bigNatAddWord# a b
+
+-- | Add two bigNats
+bigNatAdd :: BigNat -> BigNat -> BigNat
+bigNatAdd a b
+ | bigNatIsZero a = b
+ | bigNatIsZero b = a
+ | True =
+ let
+ !szA = wordArraySize# a
+ !szB = wordArraySize# b
+ !szMax = maxI# szA szB
+ !sz = szMax +# 1# -- for the potential carry
+ in withNewWordArrayTrimed# sz \mwa s ->
+ inline bignat_add mwa a b s
+
+-------------------------------------------------
+-- Multiplication
+-------------------------------------------------
+
+-- | Multiply a BigNat by a Word#
+bigNatMulWord# :: BigNat -> Word# -> BigNat
+bigNatMulWord# a w
+ | 0## <- w = bigNatZero void#
+ | 1## <- w = a
+ | bigNatIsZero a = bigNatZero void#
+ | bigNatIsOne a = bigNatFromWord# w
+ | isTrue# (bigNatSize# a ==# 1#)
+ = case timesWord2# (bigNatIndex# a 0#) w of
+ (# h, l #) -> bigNatFromWord2# h l
+ | True = withNewWordArrayTrimed# (bigNatSize# a +# 1#) \mwa s ->
+ inline bignat_mul_word mwa a w s
+
+-- | Multiply a BigNAt by a Word
+bigNatMulWord :: BigNat -> Word -> BigNat
+bigNatMulWord a (W# w) = bigNatMulWord# a w
+
+-- | Square a BigNat
+bigNatSqr :: BigNat -> BigNat
+bigNatSqr a = bigNatMul a a
+ -- This can be replaced by a backend primitive in the future (e.g. to use
+ -- GMP's mpn_sqr)
+
+-- | Multiplication (classical algorithm)
+bigNatMul :: BigNat -> BigNat -> BigNat
+bigNatMul a b
+ | bigNatSize b > bigNatSize a = bigNatMul b a -- optimize loops
+ | bigNatIsZero a = a
+ | bigNatIsZero b = b
+ | bigNatIsOne a = b
+ | bigNatIsOne b = a
+ | True =
+ let
+ !szA = wordArraySize# a
+ !szB = wordArraySize# b
+ !sz = szA +# szB
+ in withNewWordArrayTrimed# sz \mwa s->
+ inline bignat_mul mwa a b s
+
+
+-------------------------------------------------
+-- Subtraction
+-------------------------------------------------
+
+-- | Subtract a Word# from a BigNat
+--
+-- The BigNat must be bigger than the Word#.
+bigNatSubWordUnsafe# :: BigNat -> Word# -> BigNat
+bigNatSubWordUnsafe# x y
+ | 0## <- y = x
+ | True = withNewWordArrayTrimed# sz \mwa -> go mwa y 0#
+ where
+ !sz = wordArraySize# x
+
+ go mwa carry i s
+ | isTrue# (i >=# sz)
+ = s
+
+ | 0## <- carry
+ = mwaArrayCopy# mwa i x i (sz -# i) s
+
+ | True
+ = case subWordC# (indexWordArray# x i) carry of
+ (# l, c #) -> case mwaWrite# mwa i l s of
+ s1 -> go mwa (int2Word# c) (i +# 1#) s1
+
+-- | Subtract a Word# from a BigNat
+--
+-- The BigNat must be bigger than the Word#.
+bigNatSubWordUnsafe :: BigNat -> Word -> BigNat
+bigNatSubWordUnsafe x (W# y) = bigNatSubWordUnsafe# x y
+
+-- | Subtract a Word# from a BigNat
+bigNatSubWord# :: BigNat -> Word# -> (# () | BigNat #)
+bigNatSubWord# a b
+ | 0## <- b = (# | a #)
+ | bigNatIsZero a = (# () | #)
+ | True
+ = withNewWordArrayTrimedMaybe# (bigNatSize# a) \mwa s ->
+ inline bignat_sub_word mwa a b s
+
+
+-- | Subtract two BigNat (don't check if a >= b)
+bigNatSubUnsafe :: BigNat -> BigNat -> BigNat
+bigNatSubUnsafe a b
+ | bigNatIsZero b = a
+ | True =
+ let szA = wordArraySize# a
+ in withNewWordArrayTrimed# szA \mwa s->
+ case inline bignat_sub mwa a b s of
+ (# s', 0# #) -> s'
+ (# s', _ #) -> case underflow of _ -> s'
+
+-- | Subtract two BigNat
+bigNatSub :: BigNat -> BigNat -> (# () | BigNat #)
+bigNatSub a b
+ | bigNatIsZero b = (# | a #)
+ | isTrue# (bigNatSize# a <# bigNatSize# b)
+ = (# () | #)
+
+ | True
+ = withNewWordArrayTrimedMaybe# (bigNatSize# a) \mwa s ->
+ inline bignat_sub mwa a b s
+
+
+-------------------------------------------------
+-- Division
+-------------------------------------------------
+
+-- | Divide a BigNat by a Word, return the quotient
+--
+-- Require:
+-- b /= 0
+bigNatQuotWord# :: BigNat -> Word# -> BigNat
+bigNatQuotWord# a b
+ | 1## <- b = a
+ | 0## <- b = case divByZero of _ -> bigNatZero void#
+ | True =
+ let
+ sz = wordArraySize# a
+ in withNewWordArrayTrimed# sz \mwq s ->
+ inline bignat_quot_word mwq a b s
+
+-- | Divide a BigNat by a Word, return the quotient
+--
+-- Require:
+-- b /= 0
+bigNatQuotWord :: BigNat -> Word -> BigNat
+bigNatQuotWord a (W# b) = bigNatQuotWord# a b
+
+-- | Divide a BigNat by a Word, return the remainder
+--
+-- Require:
+-- b /= 0
+bigNatRemWord# :: BigNat -> Word# -> Word#
+bigNatRemWord# a b
+ | 0## <- b = 1## `remWord#` 0##
+ | 1## <- b = 0##
+ | bigNatIsZero a = 0##
+ | True = inline bignat_rem_word a b
+
+-- | Divide a BigNat by a Word, return the remainder
+--
+-- Require:
+-- b /= 0
+bigNatRemWord :: BigNat -> Word -> Word
+bigNatRemWord a (W# b) = W# (bigNatRemWord# a b)
+
+-- | QuotRem a BigNat by a Word
+--
+-- Require:
+-- b /= 0
+bigNatQuotRemWord# :: BigNat -> Word# -> (# BigNat, Word# #)
+bigNatQuotRemWord# a b
+ | 0## <- b = case divByZero of _ -> (# bigNatZero void#, 0## #)
+ | 1## <- b = (# a, 0## #)
+ | isTrue# (bigNatSize# a ==# 1#)
+ , a0 <- indexWordArray# a 0#
+ = case compareWord# a0 b of
+ LT -> (# bigNatZero void#, a0 #)
+ EQ -> (# bigNatOne void#, 0## #)
+ GT -> case quotRemWord# a0 b of
+ (# q, r #) -> (# bigNatFromWord# q, r #)
+ | True =
+ let
+ sz = wordArraySize# a
+ io s =
+ case newWordArray# sz s of { (# s1, mwq #) ->
+ case inline bignat_quotrem_word mwq a b s1 of { (# s2, r #) ->
+ case mwaTrimZeroes# mwq s2 of { s3 ->
+ case unsafeFreezeByteArray# mwq s3 of { (# s4, wq #) ->
+ (# s4, (# wq, r #) #)
+ }}}}
+ in case runRW# io of
+ (# _, (# wq,r #) #) -> (# wq, r #)
+
+
+-- | BigNat division returning (quotient,remainder)
+bigNatQuotRem# :: BigNat -> BigNat -> (# BigNat,BigNat #)
+bigNatQuotRem# a b
+ | bigNatIsZero b = case divByZero of _ -> (# bigNatZero void#, bigNatZero void# #)
+ | bigNatIsZero a = (# bigNatZero void#, bigNatZero void# #)
+ | bigNatIsOne b = (# a , bigNatZero void# #)
+ | LT <- cmp = (# bigNatZero void#, a #)
+ | EQ <- cmp = (# bigNatOne void#, bigNatZero void# #)
+ | isTrue# (szB ==# 1#) = case bigNatQuotRemWord# a (bigNatIndex# b 0#) of
+ (# q, r #) -> (# q, bigNatFromWord# r #)
+
+ | True = withNewWordArray2Trimed# szQ szR \mwq mwr s ->
+ inline bignat_quotrem mwq mwr a b s
+ where
+ cmp = bigNatCompare a b
+ szA = wordArraySize# a
+ szB = wordArraySize# b
+ szQ = 1# +# szA -# szB
+ szR = szB
+
+
+-- | BigNat division returning quotient
+bigNatQuot :: BigNat -> BigNat -> BigNat
+bigNatQuot a b
+ | bigNatIsZero b = case divByZero of _ -> bigNatZero void#
+ | bigNatIsZero a = bigNatZero void#
+ | bigNatIsOne b = a
+ | LT <- cmp = bigNatZero void#
+ | EQ <- cmp = bigNatOne void#
+ | isTrue# (szB ==# 1#) = bigNatQuotWord# a (bigNatIndex# b 0#)
+ | True = withNewWordArrayTrimed# szQ \mwq s ->
+ inline bignat_quot mwq a b s
+ where
+ cmp = bigNatCompare a b
+ szA = wordArraySize# a
+ szB = wordArraySize# b
+ szQ = 1# +# szA -# szB
+
+-- | BigNat division returning remainder
+bigNatRem :: BigNat -> BigNat -> BigNat
+bigNatRem a b
+ | bigNatIsZero b = case divByZero of _ -> bigNatZero void#
+ | bigNatIsZero a = bigNatZero void#
+ | bigNatIsOne b = bigNatZero void#
+ | LT <- cmp = a
+ | EQ <- cmp = bigNatZero void#
+ | isTrue# (szB ==# 1#) = case bigNatRemWord# a (bigNatIndex# b 0#) of
+ r -> bigNatFromWord# r
+ | True = withNewWordArrayTrimed# szR \mwr s ->
+ inline bignat_rem mwr a b s
+ where
+ cmp = bigNatCompare a b
+ szB = wordArraySize# b
+ szR = szB
+
+-------------------------------------------------
+-- GCD / LCM
+-------------------------------------------------
+
+-- Word#/Int# GCDs shouldn't be here in BigNat. However GMP provides a very fast
+-- implementation so we keep this here at least until we get a native Haskell
+-- implementation as fast as GMP's one. Note that these functions are used in
+-- `base` (e.g. in GHC.Real)
+
+-- | Greatest common divisor between two Word#
+gcdWord# :: Word# -> Word# -> Word#
+gcdWord# = bignat_gcd_word_word
+
+-- | Greatest common divisor between two Word
+gcdWord :: Word -> Word -> Word
+gcdWord (W# x) (W# y) = W# (gcdWord# x y)
+
+-- | Greatest common divisor between two Int#
+--
+-- __Warning__: result may become negative if (at least) one argument
+-- is 'minBound'
+gcdInt# :: Int# -> Int# -> Int#
+gcdInt# x y = word2Int# (gcdWord# (wordFromAbsInt# x) (wordFromAbsInt# y))
+
+-- | Greatest common divisor between two Int
+--
+-- __Warning__: result may become negative if (at least) one argument
+-- is 'minBound'
+gcdInt :: Int -> Int -> Int
+gcdInt (I# x) (I# y) = I# (gcdInt# x y)
+
+-- | Greatest common divisor
+bigNatGcd :: BigNat -> BigNat -> BigNat
+bigNatGcd a b
+ | bigNatIsZero a = b
+ | bigNatIsZero b = a
+ | bigNatIsOne a = a
+ | bigNatIsOne b = b
+ | True
+ = case (# bigNatSize# a, bigNatSize# b #) of
+ (# 1#, 1# #) -> bigNatFromWord# (gcdWord# (bigNatIndex# a 0#)
+ (bigNatIndex# b 0#))
+ (# 1#, _ #) -> bigNatFromWord# (bigNatGcdWord# b (bigNatIndex# a 0#))
+ (# _ , 1# #) -> bigNatFromWord# (bigNatGcdWord# a (bigNatIndex# b 0#))
+ _ ->
+ let
+ go wx wy = -- wx > wy
+ withNewWordArrayTrimed# (wordArraySize# wy) \mwr s ->
+ bignat_gcd mwr wx wy s
+ in case bigNatCompare a b of
+ EQ -> a
+ LT -> go b a
+ GT -> go a b
+
+-- | Greatest common divisor
+bigNatGcdWord# :: BigNat -> Word# -> Word#
+bigNatGcdWord# a b
+ | bigNatIsZero a = 0##
+ | 0## <- b = 0##
+ | bigNatIsOne a = 1##
+ | 1## <- b = 1##
+ | True = case bigNatCompareWord# a b of
+ EQ -> b
+ _ -> bignat_gcd_word a b
+
+-- | Least common multiple
+bigNatLcm :: BigNat -> BigNat -> BigNat
+bigNatLcm a b
+ | bigNatIsZero a = bigNatZero void#
+ | bigNatIsZero b = bigNatZero void#
+ | bigNatIsOne a = b
+ | bigNatIsOne b = a
+ | True
+ = case (# bigNatSize# a, bigNatSize# b #) of
+ (# 1#, 1# #) -> bigNatLcmWordWord# (bigNatIndex# a 0#) (bigNatIndex# b 0#)
+ (# 1#, _ #) -> bigNatLcmWord# b (bigNatIndex# a 0#)
+ (# _ , 1# #) -> bigNatLcmWord# a (bigNatIndex# b 0#)
+ _ -> (a `bigNatQuot` (a `bigNatGcd` b)) `bigNatMul` b
+ -- TODO: use extended GCD to get a's factor directly
+
+-- | Least common multiple with a Word#
+bigNatLcmWord# :: BigNat -> Word# -> BigNat
+bigNatLcmWord# a b
+ | bigNatIsZero a = bigNatZero void#
+ | 0## <- b = bigNatZero void#
+ | bigNatIsOne a = bigNatFromWord# b
+ | 1## <- b = a
+ | 1# <- bigNatSize# a = bigNatLcmWordWord# (bigNatIndex# a 0#) b
+ | True
+ = (a `bigNatQuotWord#` (a `bigNatGcdWord#` b)) `bigNatMulWord#` b
+ -- TODO: use extended GCD to get a's factor directly
+
+-- | Least common multiple between two Word#
+bigNatLcmWordWord# :: Word# -> Word# -> BigNat
+bigNatLcmWordWord# a b
+ | 0## <- a = bigNatZero void#
+ | 0## <- b = bigNatZero void#
+ | 1## <- a = bigNatFromWord# b
+ | 1## <- b = bigNatFromWord# a
+ | True = case (a `quotWord#` (a `gcdWord#` b)) `timesWord2#` b of
+ -- TODO: use extended GCD to get a's factor directly
+ (# h, l #) -> bigNatFromWord2# h l
+
+
+-------------------------------------------------
+-- Bitwise operations
+-------------------------------------------------
+
+-- | Bitwise OR
+bigNatOr :: BigNat -> BigNat -> BigNat
+bigNatOr a b
+ | bigNatIsZero a = b
+ | bigNatIsZero b = a
+ | True = withNewWordArray# sz \mwa s ->
+ inline bignat_or mwa a b s
+ where
+ !szA = wordArraySize# a
+ !szB = wordArraySize# b
+ !sz = maxI# szA szB
+
+-- | Bitwise OR with Word#
+bigNatOrWord# :: BigNat -> Word# -> BigNat
+bigNatOrWord# a b
+ | bigNatIsZero a = bigNatFromWord# b
+ | 0## <- b = a
+ | True =
+ let sz = wordArraySize# a
+ in withNewWordArray# sz \mwa s ->
+ case mwaArrayCopy# mwa 1# a 1# (sz -# 1#) s of
+ s' -> mwaWrite# mwa 0# (indexWordArray# a 0# `or#` b) s'
+
+-- | Bitwise AND
+bigNatAnd :: BigNat -> BigNat -> BigNat
+bigNatAnd a b
+ | bigNatIsZero a = a
+ | bigNatIsZero b = b
+ | True = withNewWordArrayTrimed# sz \mwa s ->
+ inline bignat_and mwa a b s
+ where
+ !szA = wordArraySize# a
+ !szB = wordArraySize# b
+ !sz = minI# szA szB
+
+-- | Bitwise ANDNOT
+bigNatAndNot :: BigNat -> BigNat -> BigNat
+bigNatAndNot a b
+ | bigNatIsZero a = a
+ | bigNatIsZero b = a
+ | True = withNewWordArrayTrimed# szA \mwa s ->
+ inline bignat_and_not mwa a b s
+ where
+ !szA = wordArraySize# a
+
+-- | Bitwise AND with Word#
+bigNatAndWord# :: BigNat -> Word# -> BigNat
+bigNatAndWord# a b
+ | bigNatIsZero a = a
+ | True = bigNatFromWord# (indexWordArray# a 0# `and#` b)
+
+-- | Bitwise ANDNOT with Word#
+bigNatAndNotWord# :: BigNat -> Word# -> BigNat
+bigNatAndNotWord# a b
+ | bigNatIsZero a = a
+ | szA <- bigNatSize# a
+ = withNewWordArray# szA \mwa s ->
+ -- duplicate higher limbs
+ case mwaArrayCopy# mwa 1# a 1# (szA -# 1#) s of
+ s' -> writeWordArray# mwa 0#
+ (indexWordArray# a 0# `and#` not# b) s'
+
+-- | Bitwise AND with Int#
+bigNatAndInt# :: BigNat -> Int# -> BigNat
+bigNatAndInt# a b
+ | bigNatIsZero a = a
+ | isTrue# (b >=# 0#) = bigNatAndWord# a (int2Word# b)
+ | szA <- bigNatSize# a
+ = withNewWordArray# szA \mwa s ->
+ -- duplicate higher limbs (because of sign-extension of b)
+ case mwaArrayCopy# mwa 1# a 1# (szA -# 1#) s of
+ s' -> writeWordArray# mwa 0#
+ (indexWordArray# a 0# `and#` int2Word# b) s'
+
+
+-- | Bitwise XOR
+bigNatXor :: BigNat -> BigNat -> BigNat
+bigNatXor a b
+ | bigNatIsZero a = b
+ | bigNatIsZero b = a
+ | True = withNewWordArrayTrimed# sz \mwa s ->
+ inline bignat_xor mwa a b s
+ where
+ !szA = wordArraySize# a
+ !szB = wordArraySize# b
+ !sz = maxI# szA szB
+
+-- | Bitwise XOR with Word#
+bigNatXorWord# :: BigNat -> Word# -> BigNat
+bigNatXorWord# a b
+ | bigNatIsZero a = bigNatFromWord# b
+ | 0## <- b = a
+ | True =
+ let
+ sz = wordArraySize# a
+ in withNewWordArray# sz \mwa s ->
+ case mwaArrayCopy# mwa 1# a 1# (sz -# 1#) s of
+ s' -> mwaWrite# mwa 0# (indexWordArray# a 0# `xor#` b) s'
+
+-- | PopCount for BigNat
+bigNatPopCount :: BigNat -> Word
+bigNatPopCount a = W# (bigNatPopCount# a)
+
+-- | PopCount for BigNat
+bigNatPopCount# :: BigNat -> Word#
+bigNatPopCount# a
+ | bigNatIsZero a = 0##
+ | True = inline bignat_popcount a
+
+-- | Bit shift right
+bigNatShiftR# :: BigNat -> Word# -> BigNat
+bigNatShiftR# a n
+ | 0## <- n
+ = a
+
+ | isTrue# (wordArraySize# a ==# 0#)
+ = a
+
+ | nw <- word2Int# (n `uncheckedShiftRL#` WORD_SIZE_BITS_SHIFT#)
+ , isTrue# (nw >=# wordArraySize# a)
+ = bigNatZero void#
+
+ | True
+ = let
+ !szA = wordArraySize# a
+ !nw = word2Int# (n `uncheckedShiftRL#` WORD_SIZE_BITS_SHIFT#)
+ !sz = szA -# nw
+ in withNewWordArrayTrimed# sz \mwa s ->
+ inline bignat_shiftr mwa a n s
+
+-- | Bit shift right (two's complement)
+bigNatShiftRNeg# :: BigNat -> Word# -> BigNat
+bigNatShiftRNeg# a n
+ | 0## <- n
+ = a
+
+ | isTrue# (wordArraySize# a ==# 0#)
+ = a
+
+ | nw <- word2Int# (n `uncheckedShiftRL#` WORD_SIZE_BITS_SHIFT#)
+ , isTrue# (nw >=# wordArraySize# a)
+ = bigNatZero void#
+
+ | True
+ = let
+ !szA = wordArraySize# a
+ !nw = (word2Int# n -# 1#) `uncheckedIShiftRL#` WORD_SIZE_BITS_SHIFT#
+ !sz = szA -# nw
+ in withNewWordArrayTrimed# sz \mwa s ->
+ inline bignat_shiftr_neg mwa a n s
+
+
+-- | Bit shift right
+bigNatShiftR :: BigNat -> Word -> BigNat
+bigNatShiftR a (W# n) = bigNatShiftR# a n
+
+-- | Bit shift left
+bigNatShiftL :: BigNat -> Word -> BigNat
+bigNatShiftL a (W# n) = bigNatShiftL# a n
+
+-- | Bit shift left
+bigNatShiftL# :: BigNat -> Word# -> BigNat
+bigNatShiftL# a n
+ | 0## <- n
+ = a
+
+ | isTrue# (wordArraySize# a ==# 0#)
+ = a
+
+ | True
+ = let
+ !szA = wordArraySize# a
+ !nw = word2Int# (n `uncheckedShiftRL#` WORD_SIZE_BITS_SHIFT#)
+ !nb = word2Int# (n `and#` WORD_SIZE_BITS_MASK##)
+ !sz = szA +# nw +# (nb /=# 0#)
+
+ in withNewWordArrayTrimed# sz \mwa s ->
+ inline bignat_shiftl mwa a n s
+
+
+-- | BigNat bit test
+bigNatTestBit# :: BigNat -> Word# -> Bool#
+bigNatTestBit# a n =
+ let
+ !sz = wordArraySize# a
+ !nw = word2Int# (n `uncheckedShiftRL#` WORD_SIZE_BITS_SHIFT#)
+ !nb = n `and#` WORD_SIZE_BITS_MASK##
+ in if
+ | isTrue# (nw >=# sz) -> 0#
+ | True -> testBitW# (indexWordArray# a nw) nb
+
+-- | BigNat bit test
+bigNatTestBit :: BigNat -> Word -> Bool
+bigNatTestBit a (W# n) = isTrue# (bigNatTestBit# a n)
+
+
+-- | Return a BigNat whose bit `i` is the only one set.
+--
+-- Specialized version of `bigNatShiftL (bigNatFromWord# 1##)`
+--
+bigNatBit# :: Word# -> BigNat
+bigNatBit# i
+ | 0## <- i = bigNatOne void#
+ | True =
+ let
+ !nw = word2Int# (i `uncheckedShiftRL#` WORD_SIZE_BITS_SHIFT#)
+ !nb = word2Int# (i `and#` WORD_SIZE_BITS_MASK##)
+ !sz = nw +# 1#
+ !v = 1## `uncheckedShiftL#` nb
+ in withNewWordArray# sz \mwa s ->
+ -- clear the array
+ case mwaFill# mwa 0## 0## (int2Word# sz) s of
+ -- set the bit in the most-significant word
+ s2 -> mwaWrite# mwa (sz -# 1#) v s2
+
+-- | Return a BigNat whose bit `i` is the only one set.
+--
+-- Specialized version of `bigNatShiftL (bigNatFromWord# 1##)`
+--
+bigNatBit :: Word -> BigNat
+bigNatBit (W# i) = bigNatBit# i
+
+-- | BigNat clear bit
+bigNatClearBit# :: BigNat -> Word# -> BigNat
+bigNatClearBit# a n
+ -- check the range validity and the current bit value
+ | isTrue# (bigNatTestBit# a n ==# 0#) = a
+ | True
+ = let
+ !sz = wordArraySize# a
+ !nw = word2Int# (n `uncheckedShiftRL#` WORD_SIZE_BITS_SHIFT#)
+ !nb = word2Int# (n `and#` WORD_SIZE_BITS_MASK##)
+ !nv = bigNatIndex# a nw `xor#` bitW# nb
+ in if
+ | isTrue# (sz ==# 1#)
+ -> bigNatFromWord# nv
+
+ -- special case, operating on most-significant Word
+ | 0## <- nv
+ , isTrue# (nw +# 1# ==# sz)
+ -> case sz -# (waClzAt a (sz -# 2#) +# 1#) of
+ 0# -> bigNatZero void#
+ nsz -> withNewWordArray# nsz \mwa s ->
+ mwaArrayCopy# mwa 0# a 0# nsz s
+
+ | True ->
+ withNewWordArray# sz \mwa s ->
+ case mwaArrayCopy# mwa 0# a 0# sz s of
+ s' -> writeWordArray# mwa nw nv s'
+
+-- | BigNat set bit
+bigNatSetBit# :: BigNat -> Word# -> BigNat
+bigNatSetBit# a n
+ -- check the current bit value
+ | isTrue# (bigNatTestBit# a n) = a
+ | True
+ = let
+ !sz = wordArraySize# a
+ !nw = word2Int# (n `uncheckedShiftRL#` WORD_SIZE_BITS_SHIFT#)
+ !nb = word2Int# (n `and#` WORD_SIZE_BITS_MASK##)
+ d = nw +# 1# -# sz
+ in if
+ -- result BigNat will have more limbs
+ | isTrue# (d ># 0#)
+ -> withNewWordArray# (nw +# 1#) \mwa s ->
+ case mwaArrayCopy# mwa 0# a 0# sz s of
+ s' -> case mwaFill# mwa 0## (int2Word# sz) (int2Word# (d -# 1#)) s' of
+ s'' -> writeWordArray# mwa nw (bitW# nb) s''
+
+ | nv <- bigNatIndex# a nw `or#` bitW# nb
+ -> withNewWordArray# sz \mwa s ->
+ case mwaArrayCopy# mwa 0# a 0# sz s of
+ s' -> writeWordArray# mwa nw nv s'
+
+-- | Reverse the given bit
+bigNatComplementBit# :: BigNat -> Word# -> BigNat
+bigNatComplementBit# bn i
+ | isTrue# (bigNatTestBit# bn i) = bigNatClearBit# bn i
+ | True = bigNatSetBit# bn i
+
+-------------------------------------------------
+-- Log operations
+-------------------------------------------------
+
+-- | Base 2 logarithm
+bigNatLog2# :: BigNat -> Word#
+bigNatLog2# a
+ | bigNatIsZero a = 0##
+ | True =
+ let i = int2Word# (bigNatSize# a) `minusWord#` 1##
+ in wordLog2# (bigNatIndex# a (word2Int# i))
+ `plusWord#` (i `uncheckedShiftL#` WORD_SIZE_BITS_SHIFT#)
+
+-- | Base 2 logarithm
+bigNatLog2 :: BigNat -> Word
+bigNatLog2 a = W# (bigNatLog2# a)
+
+-- | Logarithm for an arbitrary base
+bigNatLogBase# :: BigNat -> BigNat -> Word#
+bigNatLogBase# base a
+ | bigNatIsZero base || bigNatIsOne base
+ = case unexpectedValue of _ -> 0##
+
+ | 1# <- bigNatSize# base
+ , 2## <- bigNatIndex# base 0#
+ = bigNatLog2# a
+
+ -- TODO: optimize log base power of 2 (256, etc.)
+
+ | True
+ = case go base of (# _, e' #) -> e'
+ where
+ go pw = if a `bigNatLt` pw
+ then (# a, 0## #)
+ else case go (bigNatSqr pw) of
+ (# q, e #) -> if q `bigNatLt` pw
+ then (# q, 2## `timesWord#` e #)
+ else (# q `bigNatQuot` pw
+ , (2## `timesWord#` e) `plusWord#` 1## #)
+
+-- | Logarithm for an arbitrary base
+bigNatLogBase :: BigNat -> BigNat -> Word
+bigNatLogBase base a = W# (bigNatLogBase# base a)
+
+-- | Logarithm for an arbitrary base
+bigNatLogBaseWord# :: Word# -> BigNat -> Word#
+bigNatLogBaseWord# base a
+ | 0## <- base = case unexpectedValue of _ -> 0##
+ | 1## <- base = case unexpectedValue of _ -> 0##
+ | 2## <- base = bigNatLog2# a
+ -- TODO: optimize log base power of 2 (256, etc.)
+ | True = bigNatLogBase# (bigNatFromWord# base) a
+
+-- | Logarithm for an arbitrary base
+bigNatLogBaseWord :: Word -> BigNat -> Word
+bigNatLogBaseWord (W# base) a = W# (bigNatLogBaseWord# base a)
+
+-------------------------------------------------
+-- Various
+-------------------------------------------------
+
+-- | Compute the number of digits of the BigNat in the given base.
+--
+-- `base` must be > 1
+bigNatSizeInBase# :: Word# -> BigNat -> Word#
+bigNatSizeInBase# base a
+ | isTrue# (base `leWord#` 1##)
+ = case unexpectedValue of _ -> 0##
+
+ | bigNatIsZero a
+ = 0##
+
+ | True
+ = bigNatLogBaseWord# base a `plusWord#` 1##
+
+-- | Compute the number of digits of the BigNat in the given base.
+--
+-- `base` must be > 1
+bigNatSizeInBase :: Word -> BigNat -> Word
+bigNatSizeInBase (W# w) a = W# (bigNatSizeInBase# w a)
+
+-------------------------------------------------
+-- PowMod
+-------------------------------------------------
+
+-- Word# powMod shouldn't be here in BigNat. However GMP provides a very fast
+-- implementation so we keep this here at least until we get a native Haskell
+-- implementation as fast as GMP's one.
+
+powModWord# :: Word# -> Word# -> Word# -> Word#
+powModWord# = bignat_powmod_words
+
+
+-- | \"@'bigNatPowModWord#' /b/ /e/ /m/@\" computes base @/b/@ raised to
+-- exponent @/e/@ modulo @/m/@.
+bigNatPowModWord# :: BigNat -> BigNat -> Word# -> Word#
+bigNatPowModWord# !_ !_ 0## = case divByZero of _ -> 0##
+bigNatPowModWord# _ _ 1## = 0##
+bigNatPowModWord# b e m
+ | bigNatIsZero e = 1##
+ | bigNatIsZero b = 0##
+ | bigNatIsOne b = 1##
+ | True = bignat_powmod_word b e m
+
+-- | \"@'bigNatPowMod' /b/ /e/ /m/@\" computes base @/b/@ raised to
+-- exponent @/e/@ modulo @/m/@.
+bigNatPowMod :: BigNat -> BigNat -> BigNat -> BigNat
+bigNatPowMod !b !e !m
+ | (# m' | #) <- bigNatToWordMaybe# m
+ = bigNatFromWord# (bigNatPowModWord# b e m')
+ | bigNatIsZero m = case divByZero of _ -> bigNatZero void#
+ | bigNatIsOne m = bigNatFromWord# 0##
+ | bigNatIsZero e = bigNatFromWord# 1##
+ | bigNatIsZero b = bigNatFromWord# 0##
+ | bigNatIsOne b = bigNatFromWord# 1##
+ | True = withNewWordArrayTrimed# (bigNatSize# m) \mwa s ->
+ inline bignat_powmod mwa b e m s
+
+-- | Return count of trailing zero bits
+--
+-- Return 0 for zero BigNat
+bigNatCtz# :: BigNat -> Word#
+bigNatCtz# a
+ | bigNatIsZero a = 0##
+ | True = go 0# 0##
+ where
+ go i c = case indexWordArray# a i of
+ 0## -> go (i +# 1#) (c `plusWord#` WORD_SIZE_IN_BITS##)
+ w -> ctz# w `plusWord#` c
+
+-- | Return count of trailing zero bits
+--
+-- Return 0 for zero BigNat
+bigNatCtz :: BigNat -> Word
+bigNatCtz a = W# (bigNatCtz# a)
+
+
+-- | Return count of trailing zero words
+--
+-- Return 0 for zero BigNat
+bigNatCtzWord# :: BigNat -> Word#
+bigNatCtzWord# a
+ | bigNatIsZero a = 0##
+ | True = go 0# 0##
+ where
+ go i c = case indexWordArray# a i of
+ 0## -> go (i +# 1#) (c `plusWord#` 1##)
+ _ -> c
+
+-- | Return count of trailing zero words
+--
+-- Return 0 for zero BigNat
+bigNatCtzWord :: BigNat -> Word
+bigNatCtzWord a = W# (bigNatCtzWord# a)
+
+-------------------------------------------------
+-- Export to memory
+-------------------------------------------------
+
+-- | Write a BigNat in base-256 little-endian representation and return the
+-- number of bytes written.
+--
+-- Use \"@'bigNatSizeInBase' 256# /i/@\" to compute the exact number of bytes
+-- written in advance. In case of @/i/ == 0@, the function will write and report
+-- zero bytes written.
+bigNatToAddrLE# :: BigNat -> Addr# -> State# s -> (# State# s, Word# #)
+bigNatToAddrLE# a addr s0
+ | isTrue# (sz ==# 0#) = (# s0, 0## #)
+ | True = case writeMSB s0 of
+ (# s1, k #) -> case go 0# s1 of
+ s2 -> (# s2, k `plusWord#` (int2Word# li `uncheckedShiftL#` WORD_SIZE_BYTES_SHIFT#) #)
+ where
+ !sz = wordArraySize# a
+ !li = sz -# 1#
+
+ writeMSB = wordToAddrLE# (indexWordArray# a li)
+ (addr `plusAddr#` (li `uncheckedIShiftL#` WORD_SIZE_BYTES_SHIFT#))
+
+ go i s
+ | isTrue# (i <# li)
+ , off <- i `uncheckedIShiftL#` WORD_SIZE_BYTES_SHIFT#
+ , w <- indexWordArray# a i
+ = case wordWriteAddrLE# w (addr `plusAddr#` off) s of
+ s -> go (i +# 1#) s
+
+ | True
+ = s
+
+-- | Write a BigNat in base-256 big-endian representation and return the
+-- number of bytes written.
+--
+-- Use \"@'bigNatSizeInBase' 256# /i/@\" to compute the exact number of bytes
+-- written in advance. In case of @/i/ == 0@, the function will write and report
+-- zero bytes written.
+bigNatToAddrBE# :: BigNat -> Addr# -> State# s -> (# State# s, Word# #)
+bigNatToAddrBE# a addr s0
+ | isTrue# (sz ==# 0#) = (# s0, 0## #)
+ | msw <- indexWordArray# a (sz -# 1#)
+ = case wordToAddrBE# msw addr s0 of
+ (# s1, k #) -> case go (sz -# 1#) (addr `plusAddr#` word2Int# k) s1 of
+ s2 -> (# s2, k `plusWord#` (int2Word# (sz -# 1#) `uncheckedShiftL#` WORD_SIZE_BYTES_SHIFT#) #)
+ where
+ sz = wordArraySize# a
+
+ go i adr s
+ | 0# <- i
+ = s
+
+ | w <- indexWordArray# a (i -# 1#)
+ = case wordWriteAddrBE# w adr s of
+ s' -> go (i -# 1#)
+ (adr `plusAddr#` WORD_SIZE_IN_BYTES# ) s'
+
+
+-- | Write a BigNat in base-256 representation and return the
+-- number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Use \"@'bigNatSizeInBase' 256# /i/@\" to compute the exact number of bytes
+-- written in advance. In case of @/i/ == 0@, the function will write and report
+-- zero bytes written.
+bigNatToAddr# :: BigNat -> Addr# -> Bool# -> State# s -> (# State# s, Word# #)
+bigNatToAddr# a addr 0# s = bigNatToAddrLE# a addr s
+bigNatToAddr# a addr _ s = bigNatToAddrBE# a addr s
+
+-- | Write a BigNat in base-256 representation and return the
+-- number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Use \"@'bigNatSizeInBase' 256# /i/@\" to compute the exact number of bytes
+-- written in advance. In case of @/i/ == 0@, the function will write and report
+-- zero bytes written.
+bigNatToAddr :: BigNat -> Addr# -> Bool# -> IO Word
+bigNatToAddr a addr e = IO \s -> case bigNatToAddr# a addr e s of
+ (# s', w #) -> (# s', W# w #)
+
+
+
+-------------------------------------------------
+-- Import from memory
+-------------------------------------------------
+
+-- | Read a BigNat in base-256 little-endian representation from an Addr#.
+--
+-- The size is given in bytes.
+--
+-- Higher limbs equal to 0 are automatically trimed.
+bigNatFromAddrLE# :: Word# -> Addr# -> State# s -> (# State# s, BigNat #)
+bigNatFromAddrLE# 0## _ s = (# s, bigNatZero void# #)
+bigNatFromAddrLE# sz addr s =
+ let
+ !nw = sz `uncheckedShiftRL#` WORD_SIZE_BYTES_SHIFT#
+ !nb = sz `and#` WORD_SIZE_BYTES_MASK##
+
+ readMSB mwa s
+ | 0## <- nb
+ = s
+
+ | off <- word2Int# (nw `uncheckedShiftL#` WORD_SIZE_BYTES_SHIFT#)
+ = case wordFromAddrLE# nb (addr `plusAddr#` off) s of
+ (# s, w #) -> mwaWrite# mwa (word2Int# nw) w s
+
+ go mwa i s
+ | isTrue# (i ==# word2Int# nw)
+ = s
+
+ | off <- i `uncheckedIShiftL#` WORD_SIZE_BYTES_SHIFT#
+ = case wordFromAddrLE# WORD_SIZE_IN_BYTES## (addr `plusAddr#` off) s of
+ (# s, w #) -> case mwaWrite# mwa i w s of
+ s -> go mwa (i +# 1#) s
+
+ in case newWordArray# (word2Int# nw +# (word2Int# nb /=# 0#)) s of
+ (# s, mwa #) -> case readMSB mwa s of
+ s -> case go mwa 0# s of
+ s -> case mwaTrimZeroes# mwa s of
+ s -> unsafeFreezeByteArray# mwa s
+
+-- | Read a BigNat in base-256 big-endian representation from an Addr#.
+--
+-- The size is given in bytes.
+--
+-- Null higher limbs are automatically trimed.
+bigNatFromAddrBE# :: Word# -> Addr# -> State# s -> (# State# s, BigNat #)
+bigNatFromAddrBE# 0## _ s = (# s, bigNatZero void# #)
+bigNatFromAddrBE# sz addr s =
+ let
+ !nw = word2Int# (sz `uncheckedShiftRL#` WORD_SIZE_BYTES_SHIFT#)
+ !nb = sz `and#` WORD_SIZE_BYTES_MASK##
+
+ goMSB mwa s
+ | 0## <- nb
+ = s
+
+ | True
+ = case wordFromAddrBE# nb addr s of
+ (# s, w #) -> mwaWrite# mwa nw w s
+
+ go mwa i s
+ | isTrue# (i ==# nw)
+ = s
+
+ | k <- nw -# 1# -# i
+ , off <- (k `uncheckedIShiftL#` WORD_SIZE_BYTES_SHIFT#) +# word2Int# nb
+ = case wordFromAddrBE# WORD_SIZE_IN_BYTES## (addr `plusAddr#` off) s of
+ (# s, w #) -> case mwaWrite# mwa i w s of
+ s -> go mwa (i +# 1#) s
+
+ in case newWordArray# (nw +# (word2Int# nb /=# 0#)) s of
+ (# s, mwa #) -> case goMSB mwa s of
+ s -> case go mwa 0# s of
+ s -> case mwaTrimZeroes# mwa s of
+ s -> unsafeFreezeByteArray# mwa s
+
+-- | Read a BigNat in base-256 representation from an Addr#.
+--
+-- The size is given in bytes.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Null higher limbs are automatically trimed.
+bigNatFromAddr# :: Word# -> Addr# -> Bool# -> State# s -> (# State# s, BigNat #)
+bigNatFromAddr# sz addr 0# s = bigNatFromAddrLE# sz addr s
+bigNatFromAddr# sz addr _ s = bigNatFromAddrBE# sz addr s
+
+-------------------------------------------------
+-- Export to ByteArray
+-------------------------------------------------
+
+-- | Write a BigNat in base-256 little-endian representation and return the
+-- number of bytes written.
+--
+-- Use \"@'bigNatSizeInBase' 256# /i/@\" to compute the exact number of bytes
+-- written in advance. In case of @/i/ == 0@, the function will write and report
+-- zero bytes written.
+bigNatToMutableByteArrayLE# :: BigNat -> MutableByteArray# s -> Word# -> State# s -> (# State# s, Word# #)
+bigNatToMutableByteArrayLE# a mba moff s0
+ | isTrue# (sz ==# 0#) = (# s0, 0## #)
+ | True = case writeMSB s0 of
+ (# s1, k #) -> case go 0# s1 of
+ s2 -> (# s2, k `plusWord#` (int2Word# li `uncheckedShiftL#` WORD_SIZE_BYTES_SHIFT#) #)
+ where
+ !sz = wordArraySize# a
+ !li = sz -# 1#
+
+ writeMSB = wordToMutableByteArrayLE# (indexWordArray# a li)
+ mba (moff `plusWord#` int2Word# (li `uncheckedIShiftL#` WORD_SIZE_BYTES_SHIFT#))
+
+ go i s
+ | isTrue# (i <# li)
+ , off <- int2Word# i `uncheckedShiftL#` WORD_SIZE_BYTES_SHIFT#
+ , w <- indexWordArray# a i
+ = case wordWriteMutableByteArrayLE# w mba (moff `plusWord#` off) s of
+ s -> go (i +# 1#) s
+
+ | True
+ = s
+
+-- | Write a BigNat in base-256 big-endian representation and return the
+-- number of bytes written.
+--
+-- Use \"@'bigNatSizeInBase' 256# /i/@\" to compute the exact number of bytes
+-- written in advance. In case of @/i/ == 0@, the function will write and report
+-- zero bytes written.
+bigNatToMutableByteArrayBE# :: BigNat -> MutableByteArray# s -> Word# -> State# s -> (# State# s, Word# #)
+bigNatToMutableByteArrayBE# a mba moff s0
+ | isTrue# (sz ==# 0#) = (# s0, 0## #)
+ | msw <- indexWordArray# a (sz -# 1#)
+ = case wordToMutableByteArrayBE# msw mba moff s0 of
+ (# s1, k #) -> case go (sz -# 1#) k s1 of
+ s2 -> (# s2, k `plusWord#` (int2Word# (sz -# 1#) `uncheckedShiftL#` WORD_SIZE_BYTES_SHIFT#) #)
+ where
+ sz = wordArraySize# a
+
+ go i c s
+ | 0# <- i
+ = s
+
+ | w <- indexWordArray# a (i -# 1#)
+ = case wordWriteMutableByteArrayBE# w mba (moff `plusWord#` c) s of
+ s' -> go (i -# 1#)
+ (c `plusWord#` WORD_SIZE_IN_BYTES## ) s'
+
+
+-- | Write a BigNat in base-256 representation and return the
+-- number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Use \"@'bigNatSizeInBase' 256# /i/@\" to compute the exact number of bytes
+-- written in advance. In case of @/i/ == 0@, the function will write and report
+-- zero bytes written.
+bigNatToMutableByteArray# :: BigNat -> MutableByteArray# s -> Word# -> Bool# -> State# s -> (# State# s, Word# #)
+bigNatToMutableByteArray# a mba off 0# s = bigNatToMutableByteArrayLE# a mba off s
+bigNatToMutableByteArray# a mba off _ s = bigNatToMutableByteArrayBE# a mba off s
+
+-------------------------------------------------
+-- Import from ByteArray
+-------------------------------------------------
+
+-- | Read a BigNat in base-256 little-endian representation from a ByteArray#.
+--
+-- The size is given in bytes.
+--
+-- Null higher limbs are automatically trimed.
+bigNatFromByteArrayLE# :: Word# -> ByteArray# -> Word# -> State# s -> (# State# s, BigNat #)
+bigNatFromByteArrayLE# 0## _ _ s = (# s, bigNatZero void# #)
+bigNatFromByteArrayLE# sz ba moff s =
+ let
+ !nw = sz `uncheckedShiftRL#` WORD_SIZE_BYTES_SHIFT#
+ !nb = sz `and#` WORD_SIZE_BYTES_MASK##
+
+ readMSB mwa s
+ | 0## <- nb
+ = s
+
+ | off <- nw `uncheckedShiftL#` WORD_SIZE_BYTES_SHIFT#
+ = case wordFromByteArrayLE# nb ba (moff `plusWord#` off) of
+ w -> mwaWrite# mwa (word2Int# nw) w s
+
+ go mwa i s
+ | isTrue# (i `eqWord#` nw)
+ = s
+
+ | off <- i `uncheckedShiftL#` WORD_SIZE_BYTES_SHIFT#
+ = case wordFromByteArrayLE# WORD_SIZE_IN_BYTES## ba (moff `plusWord#` off) of
+ w -> case mwaWrite# mwa (word2Int# i) w s of
+ s -> go mwa (i `plusWord#` 1##) s
+
+ in case newWordArray# (word2Int# nw +# (word2Int# nb /=# 0#)) s of
+ (# s, mwa #) -> case readMSB mwa s of
+ s -> case go mwa 0## s of
+ s -> case mwaTrimZeroes# mwa s of
+ s -> unsafeFreezeByteArray# mwa s
+
+-- | Read a BigNat in base-256 big-endian representation from a ByteArray#.
+--
+-- The size is given in bytes.
+--
+-- Null higher limbs are automatically trimed.
+bigNatFromByteArrayBE# :: Word# -> ByteArray# -> Word# -> State# s -> (# State# s, BigNat #)
+bigNatFromByteArrayBE# 0## _ _ s = (# s, bigNatZero void# #)
+bigNatFromByteArrayBE# sz ba moff s =
+ let
+ !nw = sz `uncheckedShiftRL#` WORD_SIZE_BYTES_SHIFT#
+ !nb = sz `and#` WORD_SIZE_BYTES_MASK##
+
+ goMSB mwa s
+ | 0## <- nb
+ = s
+
+ | True
+ = case wordFromByteArrayBE# nb ba moff of
+ w -> mwaWrite# mwa (word2Int# nw) w s
+
+ go mwa i s
+ | isTrue# (i `eqWord#` nw)
+ = s
+
+ | k <- nw `minusWord#` 1## `minusWord#` i
+ , off <- (k `uncheckedShiftL#` WORD_SIZE_BYTES_SHIFT#) `plusWord#` nb
+ = case wordFromByteArrayBE# WORD_SIZE_IN_BYTES## ba (moff `plusWord#` off) of
+ w -> case mwaWrite# mwa (word2Int# i) w s of
+ s -> go mwa (i `plusWord#` 1##) s
+
+ in case newWordArray# (word2Int# nw +# (word2Int# nb /=# 0#)) s of
+ (# s, mwa #) -> case goMSB mwa s of
+ s -> case go mwa 0## s of
+ s -> case mwaTrimZeroes# mwa s of
+ s -> unsafeFreezeByteArray# mwa s
+
+-- | Read a BigNat in base-256 representation from a ByteArray#.
+--
+-- The size is given in bytes.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Null higher limbs are automatically trimed.
+bigNatFromByteArray# :: Word# -> ByteArray# -> Word# -> Bool# -> State# s -> (# State# s, BigNat #)
+bigNatFromByteArray# sz ba off 0# s = bigNatFromByteArrayLE# sz ba off s
+bigNatFromByteArray# sz ba off _ s = bigNatFromByteArrayBE# sz ba off s
diff --git a/libraries/ghc-bignum/src/GHC/Num/BigNat.hs-boot b/libraries/ghc-bignum/src/GHC/Num/BigNat.hs-boot
new file mode 100644
index 0000000000..5c325d074f
--- /dev/null
+++ b/libraries/ghc-bignum/src/GHC/Num/BigNat.hs-boot
@@ -0,0 +1,19 @@
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+
+module GHC.Num.BigNat where
+
+import GHC.Num.WordArray
+import GHC.Prim
+
+type BigNat = WordArray#
+
+bigNatSubUnsafe :: BigNat -> BigNat -> BigNat
+bigNatMulWord# :: BigNat -> Word# -> BigNat
+bigNatRem :: BigNat -> BigNat -> BigNat
+bigNatRemWord# :: BigNat -> Word# -> Word#
+bigNatShiftR# :: BigNat -> Word# -> BigNat
+bigNatShiftL# :: BigNat -> Word# -> BigNat
+bigNatCtz# :: BigNat -> Word#
+bigNatCtzWord# :: BigNat -> Word#
diff --git a/libraries/ghc-bignum/src/GHC/Num/BigNat/Check.hs b/libraries/ghc-bignum/src/GHC/Num/BigNat/Check.hs
new file mode 100644
index 0000000000..aad7d903ff
--- /dev/null
+++ b/libraries/ghc-bignum/src/GHC/Num/BigNat/Check.hs
@@ -0,0 +1,456 @@
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE GHCForeignImportPrim #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE UnliftedFFITypes #-}
+{-# LANGUAGE NegativeLiterals #-}
+{-# LANGUAGE ForeignFunctionInterface #-}
+{-# OPTIONS_GHC -Wno-name-shadowing #-}
+{-# OPTIONS_GHC -ddump-simpl -ddump-to-file #-}
+
+-- | Check Native implementation against another backend
+module GHC.Num.BigNat.Check where
+
+import GHC.Prim
+import GHC.Types
+import GHC.Num.WordArray
+import GHC.Num.Primitives
+import qualified GHC.Num.BigNat.Native as Native
+
+#if defined(BIGNUM_NATIVE)
+#error You can't validate Native backed against itself. Choose another backend (e.g. gmp, ffi)
+
+#elif defined(BIGNUM_FFI)
+import qualified GHC.Num.BigNat.FFI as Other
+
+#elif defined(BIGNUM_GMP)
+import qualified GHC.Num.BigNat.GMP as Other
+
+#else
+#error Undefined BigNat backend. Use a flag to select it (e.g. gmp, native, ffi)`
+#endif
+
+default ()
+
+bignat_compare
+ :: WordArray#
+ -> WordArray#
+ -> Int#
+bignat_compare a b =
+ let
+ gr = Other.bignat_compare a b
+ nr = Native.bignat_compare a b
+ in case gr ==# nr of
+ 0# -> case unexpectedValue of I# x -> x
+ _ -> gr
+
+mwaCompare
+ :: MutableWordArray# s
+ -> MutableWordArray# s
+ -> State# s
+ -> (# State# s, Bool# #)
+mwaCompare mwa mwb s =
+ case mwaSize# mwa s of
+ (# s, szA #) -> case mwaSize# mwb s of
+ (# s, szB #) -> case szA ==# szB of
+ 0# -> (# s, 0# #)
+ _ -> let
+ go i s
+ | isTrue# (i <# 0#) = (# s, 1# #)
+ | True =
+ case readWordArray# mwa i s of
+ (# s, a #) -> case readWordArray# mwb i s of
+ (# s, b #) -> case a `eqWord#` b of
+ 0# -> (# s, 0# #)
+ _ -> go (i -# 1#) s
+ in go (szA -# 1#) s
+
+mwaCompareOp
+ :: MutableWordArray# s
+ -> (MutableWordArray# s -> State# s -> State# s)
+ -> (MutableWordArray# s -> State# s -> State# s)
+ -> State# s
+ -> State# s
+mwaCompareOp mwa f g s =
+ case mwaSize# mwa s of { (# s, sz #) ->
+ case newWordArray# sz s of { (# s, mwb #) ->
+ case f mwa s of { s ->
+ case g mwb s of { s ->
+ case mwaTrimZeroes# mwa s of { s ->
+ case mwaTrimZeroes# mwb s of { s ->
+ case mwaCompare mwa mwb s of
+ (# s, 0# #) -> case unexpectedValue of _ -> s
+ (# s, _ #) -> s
+ }}}}}}
+
+mwaCompareOp2
+ :: MutableWordArray# s
+ -> MutableWordArray# s
+ -> (MutableWordArray# s -> MutableWordArray# s -> State# s -> State# s)
+ -> (MutableWordArray# s -> MutableWordArray# s -> State# s -> State# s)
+ -> State# s
+ -> State# s
+mwaCompareOp2 mwa mwb f g s =
+ case mwaSize# mwa s of { (# s, szA #) ->
+ case mwaSize# mwb s of { (# s, szB #) ->
+ case newWordArray# szA s of { (# s, mwa' #) ->
+ case newWordArray# szB s of { (# s, mwb' #) ->
+ case f mwa mwb s of { s ->
+ case g mwa' mwb' s of { s ->
+ case mwaTrimZeroes# mwa s of { s ->
+ case mwaTrimZeroes# mwb s of { s ->
+ case mwaTrimZeroes# mwa' s of { s ->
+ case mwaTrimZeroes# mwb' s of { s ->
+ case mwaCompare mwa mwa' s of { (# s, ba #) ->
+ case mwaCompare mwb mwb' s of { (# s, bb #) ->
+ case ba &&# bb of
+ 0# -> case unexpectedValue of _ -> s
+ _ -> s
+ }}}}}}}}}}}}
+
+mwaCompareOpBool
+ :: MutableWordArray# s
+ -> (MutableWordArray# s -> State# s -> (#State# s, Bool# #))
+ -> (MutableWordArray# s -> State# s -> (#State# s, Bool# #))
+ -> State# s
+ -> (# State# s, Bool# #)
+mwaCompareOpBool mwa f g s =
+ case mwaSize# mwa s of { (# s, sz #) ->
+ case newWordArray# sz s of { (# s, mwb #) ->
+ case f mwa s of { (# s, ra #) ->
+ case g mwb s of { (# s, rb #) ->
+ case ra ==# rb of
+ 0# -> case unexpectedValue of _ -> (# s, ra #)
+ _ -> case (ra ==# 1#) of -- don't compare MWAs if overflow signaled!
+ 1# -> (# s, ra #)
+ _ -> case mwaTrimZeroes# mwa s of { s ->
+ case mwaTrimZeroes# mwb s of { s ->
+ case mwaCompare mwa mwb s of
+ (# s, 0# #) -> case unexpectedValue of _ -> (# s, ra #)
+ _ -> (# s, ra #)
+ }}}}}}
+
+mwaCompareOpWord
+ :: MutableWordArray# s
+ -> (MutableWordArray# s -> State# s -> (#State# s, Word# #))
+ -> (MutableWordArray# s -> State# s -> (#State# s, Word# #))
+ -> State# s
+ -> (# State# s, Word# #)
+mwaCompareOpWord mwa f g s =
+ case mwaSize# mwa s of { (# s, sz #) ->
+ case newWordArray# sz s of { (# s, mwb #) ->
+ case f mwa s of { (# s, ra #) ->
+ case g mwb s of { (# s, rb #) ->
+ case mwaTrimZeroes# mwa s of { s ->
+ case mwaTrimZeroes# mwb s of { s ->
+ case mwaCompare mwa mwb s of
+ (# s, b #) -> case b &&# (ra `eqWord#` rb) of
+ 0# -> case unexpectedValue of _ -> (# s, ra #)
+ _ -> (# s, ra #)
+ }}}}}}
+
+bignat_add
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_add mwa wa wb
+ = mwaCompareOp mwa
+ (\m -> Other.bignat_add m wa wb)
+ (\m -> Native.bignat_add m wa wb)
+
+bignat_add_word
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_add_word mwa wa b
+ = mwaCompareOp mwa
+ (\m -> Other.bignat_add_word m wa b)
+ (\m -> Native.bignat_add_word m wa b)
+
+bignat_mul_word
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_mul_word mwa wa b
+ = mwaCompareOp mwa
+ (\m -> Other.bignat_mul_word m wa b)
+ (\m -> Native.bignat_mul_word m wa b)
+
+bignat_sub
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> (# State# RealWorld, Bool# #)
+bignat_sub mwa wa wb
+ = mwaCompareOpBool mwa
+ (\m -> Other.bignat_sub m wa wb)
+ (\m -> Native.bignat_sub m wa wb)
+
+bignat_sub_word
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> (# State# RealWorld, Bool# #)
+bignat_sub_word mwa wa b
+ = mwaCompareOpBool mwa
+ (\m -> Other.bignat_sub_word m wa b)
+ (\m -> Native.bignat_sub_word m wa b)
+
+bignat_mul
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_mul mwa wa wb
+ = mwaCompareOp mwa
+ (\m -> Other.bignat_mul m wa wb)
+ (\m -> Native.bignat_mul m wa wb)
+
+bignat_popcount :: WordArray# -> Word#
+bignat_popcount wa =
+ let
+ gr = Other.bignat_popcount wa
+ nr = Native.bignat_popcount wa
+ in case gr `eqWord#` nr of
+ 0# -> 1## `quotWord#` 0##
+ _ -> gr
+
+bignat_shiftl
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_shiftl mwa wa n
+ = mwaCompareOp mwa
+ (\m -> Other.bignat_shiftl m wa n)
+ (\m -> Native.bignat_shiftl m wa n)
+
+bignat_shiftr
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_shiftr mwa wa n
+ = mwaCompareOp mwa
+ (\m -> Other.bignat_shiftr m wa n)
+ (\m -> Native.bignat_shiftr m wa n)
+
+bignat_shiftr_neg
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_shiftr_neg mwa wa n
+ = mwaCompareOp mwa
+ (\m -> Other.bignat_shiftr_neg m wa n)
+ (\m -> Native.bignat_shiftr_neg m wa n)
+
+bignat_or
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_or mwa wa wb
+ = mwaCompareOp mwa
+ (\m -> Other.bignat_or m wa wb)
+ (\m -> Native.bignat_or m wa wb)
+
+bignat_xor
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_xor mwa wa wb
+ = mwaCompareOp mwa
+ (\m -> Other.bignat_xor m wa wb)
+ (\m -> Native.bignat_xor m wa wb)
+
+bignat_and
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_and mwa wa wb
+ = mwaCompareOp mwa
+ (\m -> Other.bignat_and m wa wb)
+ (\m -> Native.bignat_and m wa wb)
+
+bignat_and_not
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_and_not mwa wa wb
+ = mwaCompareOp mwa
+ (\m -> Other.bignat_and_not m wa wb)
+ (\m -> Native.bignat_and_not m wa wb)
+
+bignat_quotrem
+ :: MutableWordArray# RealWorld
+ -> MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_quotrem mwq mwr wa wb
+ = mwaCompareOp2 mwq mwr
+ (\m1 m2 -> Other.bignat_quotrem m1 m2 wa wb)
+ (\m1 m2 -> Native.bignat_quotrem m1 m2 wa wb)
+
+bignat_quot
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_quot mwq wa wb
+ = mwaCompareOp mwq
+ (\m -> Other.bignat_quot m wa wb)
+ (\m -> Native.bignat_quot m wa wb)
+
+bignat_rem
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_rem mwr wa wb
+ = mwaCompareOp mwr
+ (\m -> Other.bignat_rem m wa wb)
+ (\m -> Native.bignat_rem m wa wb)
+
+bignat_quotrem_word
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> (# State# RealWorld, Word# #)
+bignat_quotrem_word mwq wa b
+ = mwaCompareOpWord mwq
+ (\m -> Other.bignat_quotrem_word m wa b)
+ (\m -> Native.bignat_quotrem_word m wa b)
+
+bignat_quot_word
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_quot_word mwq wa b
+ = mwaCompareOp mwq
+ (\m -> Other.bignat_quot_word m wa b)
+ (\m -> Native.bignat_quot_word m wa b)
+
+bignat_rem_word
+ :: WordArray#
+ -> Word#
+ -> Word#
+bignat_rem_word wa b =
+ let
+ gr = Other.bignat_rem_word wa b
+ nr = Native.bignat_rem_word wa b
+ in case gr `eqWord#` nr of
+ 1# -> gr
+ _ -> case unexpectedValue of
+ W# e -> e
+
+bignat_gcd
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_gcd mwr wa wb
+ = mwaCompareOp mwr
+ (\m -> Other.bignat_gcd m wa wb)
+ (\m -> Native.bignat_gcd m wa wb)
+
+bignat_gcd_word
+ :: WordArray#
+ -> Word#
+ -> Word#
+bignat_gcd_word wa b =
+ let
+ gr = Other.bignat_gcd_word wa b
+ nr = Native.bignat_gcd_word wa b
+ in case gr `eqWord#` nr of
+ 1# -> gr
+ _ -> case unexpectedValue of
+ W# e -> e
+
+bignat_gcd_word_word
+ :: Word#
+ -> Word#
+ -> Word#
+bignat_gcd_word_word a b =
+ let
+ gr = Other.bignat_gcd_word_word a b
+ nr = Native.bignat_gcd_word_word a b
+ in case gr `eqWord#` nr of
+ 1# -> gr
+ _ -> case unexpectedValue of
+ W# e -> e
+
+bignat_encode_double :: WordArray# -> Int# -> Double#
+bignat_encode_double a e =
+ let
+ gr = Other.bignat_encode_double a e
+ nr = Native.bignat_encode_double a e
+ in case gr ==## nr of
+ 1# -> gr
+ _ -> case unexpectedValue of
+ _ -> gr
+
+bignat_powmod_word :: WordArray# -> WordArray# -> Word# -> Word#
+bignat_powmod_word b e m =
+ let
+ gr = Other.bignat_powmod_word b e m
+ nr = Native.bignat_powmod_word b e m
+ in case gr `eqWord#` nr of
+ 1# -> gr
+ _ -> case unexpectedValue of
+ W# e -> e
+
+bignat_powmod
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_powmod r b e m
+ = mwaCompareOp r
+ (\r' -> Other.bignat_powmod r' b e m)
+ (\r' -> Native.bignat_powmod r' b e m)
+
+bignat_powmod_words
+ :: Word#
+ -> Word#
+ -> Word#
+ -> Word#
+bignat_powmod_words b e m =
+ let
+ gr = Other.bignat_powmod_words b e m
+ nr = Native.bignat_powmod_words b e m
+ in case gr `eqWord#` nr of
+ 1# -> gr
+ _ -> case unexpectedValue of
+ W# e -> e
diff --git a/libraries/ghc-bignum/src/GHC/Num/BigNat/FFI.hs b/libraries/ghc-bignum/src/GHC/Num/BigNat/FFI.hs
new file mode 100644
index 0000000000..3ef2f7046c
--- /dev/null
+++ b/libraries/ghc-bignum/src/GHC/Num/BigNat/FFI.hs
@@ -0,0 +1,581 @@
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE GHCForeignImportPrim #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE UnliftedFFITypes #-}
+{-# LANGUAGE NegativeLiterals #-}
+{-# LANGUAGE ForeignFunctionInterface #-}
+
+-- | External BigNat backend that directly call FFI operations.
+--
+-- This backend can be useful for specific compilers such as GHCJS or Asterius
+-- that replace bignat foreign calls with calls to the native platform bignat
+-- library (e.g. JavaScript's BigInt). You can also link an extra object
+-- providing the implementation.
+module GHC.Num.BigNat.FFI where
+
+import GHC.Prim
+import GHC.Types
+import GHC.Num.WordArray
+import GHC.Num.Primitives
+
+default ()
+
+-- | Compare two non-zero BigNat of the same length
+--
+-- Return:
+-- < 0 ==> LT
+-- == 0 ==> EQ
+-- > 0 ==> GT
+bignat_compare
+ :: WordArray#
+ -> WordArray#
+ -> Int#
+bignat_compare = ghc_bignat_compare
+
+foreign import ccall unsafe ghc_bignat_compare
+ :: WordArray#
+ -> WordArray#
+ -> Int#
+
+-- | Add two non-zero BigNat
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: max (size a, size b) + 1
+--
+-- The potential 0 most-significant Word (i.e. the potential carry) will be
+-- removed by the caller if it is not already done by the backend.
+bignat_add
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_add mwa wa wb s
+ = ioVoid (ghc_bignat_add mwa wa wb) s
+
+foreign import ccall unsafe ghc_bignat_add
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> IO ()
+
+-- | Add a non-zero BigNat and a non-zero Word#
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: size a + 1
+--
+-- The potential 0 most-significant Word (i.e. the potential carry) will be
+-- removed by the caller if it is not already done by the backend.
+bignat_add_word
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_add_word mwa wa b s =
+ ioVoid (ghc_bignat_add_word mwa wa b) s
+
+foreign import ccall unsafe ghc_bignat_add_word
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> Word#
+ -> IO ()
+
+-- | Multiply a non-zero BigNat and a non-zero Word#
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: size a + 1
+--
+-- The potential 0 most-significant Word (i.e. the potential carry) will be
+-- removed by the caller if it is not already done by the backend.
+bignat_mul_word
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_mul_word mwa wa b s =
+ ioVoid (ghc_bignat_mul_word mwa wa b) s
+
+foreign import ccall unsafe ghc_bignat_mul_word
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> Word#
+ -> IO ()
+
+-- | Sub two non-zero BigNat
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: size a
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+--
+-- Return True to indicate overflow.
+bignat_sub
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> (# State# RealWorld, Bool# #)
+bignat_sub mwa wa wb s = ioBool (ghc_bignat_sub mwa wa wb) s
+
+foreign import ccall unsafe ghc_bignat_sub
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> IO Bool
+
+-- | Sub a non-zero word from a non-zero BigNat
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: size a
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+--
+-- Return True to indicate overflow.
+bignat_sub_word
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> (# State# RealWorld, Bool# #)
+bignat_sub_word mwa wa b s = ioBool (ghc_bignat_sub_word mwa wa b) s
+
+foreign import ccall unsafe ghc_bignat_sub_word
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> Word#
+ -> IO Bool
+
+-- | Multiply two non-zero BigNat
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: size a+size b
+--
+-- The potential 0 most-significant Word (i.e. the potential carry) will be
+-- removed by the caller if it is not already done by the backend.
+bignat_mul
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_mul mwa wa wb s = ioVoid (ghc_bignat_mul mwa wa wb) s
+
+foreign import ccall unsafe ghc_bignat_mul
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> IO ()
+
+-- | PopCount of a non-zero BigNat
+bignat_popcount :: WordArray# -> Word#
+bignat_popcount = ghc_bignat_popcount
+
+foreign import ccall unsafe ghc_bignat_popcount
+ :: WordArray#
+ -> Word#
+
+-- | Left-shift a non-zero BigNat by a non-zero amount of bits
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: size a + required new limbs
+--
+-- The potential 0 most-significant Word (i.e. the potential carry) will be
+-- removed by the caller if it is not already done by the backend.
+bignat_shiftl
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_shiftl mwa wa n s = ioVoid (ghc_bignat_shiftl mwa wa n) s
+
+foreign import ccall unsafe ghc_bignat_shiftl
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> IO ()
+
+-- | Right-shift a non-zero BigNat by a non-zero amount of bits
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: required limbs
+--
+-- The potential 0 most-significant Word (i.e. the potential carry) will be
+-- removed by the caller if it is not already done by the backend.
+bignat_shiftr
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_shiftr mwa wa n s = ioVoid (ghc_bignat_shiftr mwa wa n) s
+
+foreign import ccall unsafe ghc_bignat_shiftr
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> IO ()
+
+-- | Right-shift a non-zero BigNat by a non-zero amount of bits by first
+-- converting it into its two's complement representation and then again after
+-- the arithmetic shift.
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: required limbs
+--
+-- The potential 0 most-significant Words (i.e. the potential carry) will be
+-- removed by the caller if it is not already done by the backend.
+bignat_shiftr_neg
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_shiftr_neg mwa wa n s = ioVoid (ghc_bignat_shiftr_neg mwa wa n) s
+
+foreign import ccall unsafe ghc_bignat_shiftr_neg
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> IO ()
+
+
+-- | OR two non-zero BigNat
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: max (size a, size b)
+bignat_or
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_or #-}
+bignat_or mwa wa wb s = ioVoid (ghc_bignat_or mwa wa wb) s
+
+foreign import ccall unsafe ghc_bignat_or
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> IO ()
+
+-- | XOR two non-zero BigNat
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: max (size a, size b)
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+bignat_xor
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_xor #-}
+bignat_xor mwa wa wb s = ioVoid (ghc_bignat_xor mwa wa wb) s
+
+foreign import ccall unsafe ghc_bignat_xor
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> IO ()
+
+-- | AND two non-zero BigNat
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: min (size a, size b)
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+bignat_and
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_and #-}
+bignat_and mwa wa wb s = ioVoid (ghc_bignat_and mwa wa wb) s
+
+foreign import ccall unsafe ghc_bignat_and
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> IO ()
+
+-- | ANDNOT two non-zero BigNat
+--
+-- Result is to be stored in the MutableWordArray#.
+-- The latter has size: size a
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+bignat_and_not
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_and_not #-}
+bignat_and_not mwa wa wb s = ioVoid (ghc_bignat_and_not mwa wa wb) s
+
+foreign import ccall unsafe ghc_bignat_and_not
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> IO ()
+
+-- | QuotRem of two non-zero BigNat
+--
+-- Result quotient and remainder are to be stored in the MutableWordArray#.
+-- The first one (quotient) has size: size(A)-size(B)+1
+-- The second one (remainder) has size: size(b)
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+bignat_quotrem
+ :: MutableWordArray# RealWorld -- ^ Quotient
+ -> MutableWordArray# RealWorld -- ^ Remainder
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_quotrem mwq mwr wa wb s =
+ ioVoid (ghc_bignat_quotrem mwq mwr wa wb) s
+
+foreign import ccall unsafe ghc_bignat_quotrem
+ :: MutableWordArray# RealWorld
+ -> MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> IO ()
+
+-- | Quotient of two non-zero BigNat
+--
+-- Result quotient is to be stored in the MutableWordArray#.
+-- The latter has size: size(A)-size(B)+1
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+bignat_quot
+ :: MutableWordArray# RealWorld -- ^ Quotient
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_quot mwq wa wb s =
+ ioVoid (ghc_bignat_quot mwq wa wb) s
+
+foreign import ccall unsafe ghc_bignat_quot
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> IO ()
+
+-- | Remainder of two non-zero BigNat
+--
+-- Result remainder is to be stored in the MutableWordArray#.
+-- The latter has size: size(B)
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+bignat_rem
+ :: MutableWordArray# RealWorld -- ^ Quotient
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_rem mwr wa wb s =
+ ioVoid (ghc_bignat_rem mwr wa wb) s
+
+foreign import ccall unsafe ghc_bignat_rem
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> IO ()
+
+-- | QuotRem of a non-zero BigNat and a non-zero Word
+--
+-- Result quotient is to be stored in the MutableWordArray#.
+-- The latter has size: size(A)
+--
+-- The remainder is returned.
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+bignat_quotrem_word
+ :: MutableWordArray# RealWorld -- ^ Quotient
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> (# State# RealWorld, Word# #)
+bignat_quotrem_word mwq wa b s =
+ ioWord# (ghc_bignat_quotrem_word mwq wa b) s
+
+foreign import ccall unsafe ghc_bignat_quotrem_word
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> IO Word
+
+-- | Quot of a non-zero BigNat and a non-zero Word
+--
+-- Result quotient is to be stored in the MutableWordArray#.
+-- The latter has size: size(A)
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+bignat_quot_word
+ :: MutableWordArray# RealWorld -- ^ Quotient
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_quot_word mwq wa b s =
+ ioVoid (ghc_bignat_quot_word mwq wa b) s
+
+foreign import ccall unsafe ghc_bignat_quot_word
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> IO ()
+
+-- | Remainder of a non-zero BigNat and a non-zero Word
+--
+-- The remainder is returned.
+bignat_rem_word
+ :: WordArray#
+ -> Word#
+ -> Word#
+bignat_rem_word = ghc_bignat_rem_word
+
+foreign import ccall unsafe ghc_bignat_rem_word
+ :: WordArray#
+ -> Word#
+ -> Word#
+
+
+-- | Greatest common divisor (GCD) of two non-zero and non-one BigNat
+--
+-- Result GCD is to be stored in the MutableWordArray#.
+-- The latter has size: size(B)
+-- The first WordArray# is greater than the second WordArray#.
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+bignat_gcd
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_gcd mwr wa wb s =
+ ioVoid (ghc_bignat_gcd mwr wa wb) s
+
+foreign import ccall unsafe ghc_bignat_gcd
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> IO ()
+
+-- | Greatest common divisor (GCD) of a non-zero/non-one BigNat and a
+-- non-zero/non-one Word#
+--
+-- Result GCD is returned
+bignat_gcd_word
+ :: WordArray#
+ -> Word#
+ -> Word#
+bignat_gcd_word = ghc_bignat_gcd_word
+
+foreign import ccall unsafe ghc_bignat_gcd_word
+ :: WordArray#
+ -> Word#
+ -> Word#
+
+-- | Greatest common divisor (GCD) of two Word#
+--
+-- Result GCD is returned
+bignat_gcd_word_word
+ :: Word#
+ -> Word#
+ -> Word#
+bignat_gcd_word_word = ghc_bignat_gcd_word_word
+
+foreign import ccall unsafe ghc_bignat_gcd_word_word
+ :: Word#
+ -> Word#
+ -> Word#
+
+-- | Encode (# BigNat mantissa, Int# exponent #) into a Double#
+bignat_encode_double :: WordArray# -> Int# -> Double#
+bignat_encode_double = ghc_bignat_encode_double
+
+foreign import ccall unsafe ghc_bignat_encode_double
+ :: WordArray#
+ -> Int#
+ -> Double#
+
+-- | \"@'bignat_powmod_word' /b/ /e/ /m/@\" computes base @/b/@ raised to
+-- exponent @/e/@ modulo @/m/@.
+--
+-- b > 1
+-- e > 0
+-- m > 1
+bignat_powmod_word :: WordArray# -> WordArray# -> Word# -> Word#
+bignat_powmod_word = ghc_bignat_powmod_word
+
+foreign import ccall unsafe ghc_bignat_powmod_word
+ :: WordArray# -> WordArray# -> Word# -> Word#
+
+-- | \"@'bignat_powmod' r /b/ /e/ /m/@\" computes base @/b/@ raised to
+-- exponent @/e/@ modulo @/m/@.
+--
+-- b > 1
+-- e > 0
+-- m > 1
+--
+-- Result is to be stored in the MutableWordArray# (which size is equal to the
+-- one of m).
+--
+-- The potential 0 most-significant Words will be removed by the caller if it is
+-- not already done by the backend.
+bignat_powmod
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_powmod r b e m s =
+ ioVoid (ghc_bignat_powmod r b e m) s
+
+foreign import ccall unsafe ghc_bignat_powmod
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> WordArray#
+ -> IO ()
+
+-- | \"@'bignat_powmod' /b/ /e/ /m/@\" computes base @/b/@ raised to
+-- exponent @/e/@ modulo @/m/@.
+--
+-- b > 1
+-- e > 0
+-- m > 1
+bignat_powmod_words
+ :: Word#
+ -> Word#
+ -> Word#
+ -> Word#
+bignat_powmod_words = ghc_bignat_powmod_words
+
+foreign import ccall unsafe ghc_bignat_powmod_words
+ :: Word# -> Word# -> Word# -> Word#
+
diff --git a/libraries/ghc-bignum/src/GHC/Num/BigNat/GMP.hs b/libraries/ghc-bignum/src/GHC/Num/BigNat/GMP.hs
new file mode 100644
index 0000000000..cb1fe500d9
--- /dev/null
+++ b/libraries/ghc-bignum/src/GHC/Num/BigNat/GMP.hs
@@ -0,0 +1,498 @@
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE GHCForeignImportPrim #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE UnliftedFFITypes #-}
+{-# LANGUAGE NegativeLiterals #-}
+{-# LANGUAGE BlockArguments #-}
+
+-- | Backend based on the GNU GMP library.
+--
+-- This has been adapted from the legacy `integer-gmp` package written by
+-- Herbert Valerio Riedel.
+module GHC.Num.BigNat.GMP where
+
+#include "MachDeps.h"
+#include "WordSize.h"
+
+import GHC.Num.WordArray
+import GHC.Num.Primitives
+import GHC.Prim
+import GHC.Types
+
+default ()
+
+----------------------------------------------------------------------------
+-- type definitions
+
+-- NB: all code assumes GMP_LIMB_BITS == WORD_SIZE_IN_BITS
+-- The C99 code in cbits/gmp_wrappers.c will fail to compile if this doesn't hold
+
+-- | Type representing a GMP Limb
+type GmpLimb = Word -- actually, 'CULong'
+type GmpLimb# = Word#
+
+-- | Count of 'GmpLimb's, must be positive (unless specified otherwise).
+type GmpSize = Int -- actually, a 'CLong'
+type GmpSize# = Int#
+
+narrowGmpSize# :: Int# -> Int#
+#if SIZEOF_LONG == SIZEOF_HSWORD
+narrowGmpSize# x = x
+#elif (SIZEOF_LONG == 4) && (SIZEOF_HSWORD == 8)
+-- On IL32P64 (i.e. Win64), we have to be careful with CLong not being
+-- 64bit. This is mostly an issue on values returned from C functions
+-- due to sign-extension.
+narrowGmpSize# = narrow32Int#
+#endif
+
+narrowCInt# :: Int# -> Int#
+narrowCInt# = narrow32Int#
+
+bignat_compare :: WordArray# -> WordArray# -> Int#
+bignat_compare x y = narrowCInt# (c_mpn_cmp x y (wordArraySize# x))
+
+bignat_add
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_add #-}
+bignat_add mwa wa wb s
+ -- weird GMP requirement
+ | isTrue# (wordArraySize# wb ># wordArraySize# wa)
+ = bignat_add mwa wb wa s
+
+ | True
+ = do
+ case ioWord# (c_mpn_add mwa wa (wordArraySize# wa) wb (wordArraySize# wb)) s of
+ (# s', c #) -> mwaWriteMostSignificant mwa c s'
+
+bignat_add_word
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_add_word #-}
+bignat_add_word mwa wa b s = do
+ case ioWord# (c_mpn_add_1 mwa wa (wordArraySize# wa) b) s of
+ (# s', c #) -> mwaWriteMostSignificant mwa c s'
+
+bignat_sub
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> (# State# RealWorld, Bool# #)
+{-# INLINE bignat_sub #-}
+bignat_sub mwa wa wb s =
+ case ioWord# (c_mpn_sub mwa wa (wordArraySize# wa) wb (wordArraySize# wb)) s of
+ (# s', 0## #) -> (# s', 0# #)
+ (# s', _ #) -> (# s', 1# #)
+
+bignat_sub_word
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> (# State# RealWorld, Bool# #)
+{-# INLINE bignat_sub_word #-}
+bignat_sub_word mwa wa b s =
+ case ioWord# (c_mpn_sub_1 mwa wa (wordArraySize# wa) b) s of
+ (# s', 0## #) -> (# s', 0# #)
+ (# s', _ #) -> (# s', 1# #)
+
+bignat_mul
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_mul #-}
+bignat_mul mwa wa wb s = do
+ case ioWord# (c_mpn_mul mwa wa (wordArraySize# wa) wb (wordArraySize# wb)) s of
+ (# s', _msl #) -> s' -- we don't care about the most-significant
+ -- limb. The caller shrink the mwa if
+ -- necessary anyway.
+
+bignat_mul_word
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_mul_word #-}
+bignat_mul_word mwa wa b s =
+ case ioWord# (c_mpn_mul_1 mwa wa (wordArraySize# wa) b) s of
+ (# s', c #) -> mwaWriteMostSignificant mwa c s'
+
+bignat_popcount :: WordArray# -> Word#
+{-# INLINE bignat_popcount #-}
+bignat_popcount wa = c_mpn_popcount wa (wordArraySize# wa)
+
+
+bignat_shiftl
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_shiftl #-}
+bignat_shiftl mwa wa n s =
+ case ioWord# (c_mpn_lshift mwa wa (wordArraySize# wa) n) s of
+ (# s', _msl #) -> s' -- we don't care about the most-significant
+ -- limb. The caller shrink the mwa if
+ -- necessary anyway.
+
+bignat_shiftr
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_shiftr #-}
+bignat_shiftr mwa wa n s =
+ case ioWord# (c_mpn_rshift mwa wa (wordArraySize# wa) n) s of
+ (# s', _msl #) -> s' -- we don't care about the most-significant
+ -- limb. The caller shrink the mwa if
+ -- necessary anyway.
+
+bignat_or
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_or #-}
+bignat_or mwa wa wb s1
+ | isTrue# (szA >=# szB) = go wa szA wb szB s1
+ | True = go wb szB wa szA s1
+ where
+ !szA = wordArraySize# wa
+ !szB = wordArraySize# wb
+ -- nx >= ny
+ go wx nx wy ny s = case ioVoid (c_mpn_ior_n mwa wx wy ny) s of
+ s' -> mwaArrayCopy# mwa ny wx ny (nx -# ny) s'
+
+bignat_xor
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_xor #-}
+bignat_xor mwa wa wb s1
+ | isTrue# (szA >=# szB) = go wa szA wb szB s1
+ | True = go wb szB wa szA s1
+ where
+ !szA = wordArraySize# wa
+ !szB = wordArraySize# wb
+ -- nx >= ny
+ go wx nx wy ny s = case ioVoid (c_mpn_xor_n mwa wx wy ny) s of
+ s' -> mwaArrayCopy# mwa ny wx ny (nx -# ny) s'
+
+bignat_and
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_and #-}
+bignat_and mwa wa wb s = ioVoid (c_mpn_and_n mwa wa wb sz) s
+ where
+ !szA = wordArraySize# wa
+ !szB = wordArraySize# wb
+ !sz = minI# szA szB
+
+bignat_and_not
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+{-# INLINE bignat_and_not #-}
+bignat_and_not mwa wa wb s =
+ case ioVoid (c_mpn_andn_n mwa wa wb n) s of
+ s' -> mwaArrayCopy# mwa szB wa szB (szA -# szB) s'
+ where
+ !szA = wordArraySize# wa
+ !szB = wordArraySize# wb
+ !n = minI# szA szB
+
+bignat_quotrem
+ :: MutableWordArray# RealWorld
+ -> MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_quotrem mwq mwr wa wb s =
+ ioVoid (c_mpn_tdiv_qr mwq mwr 0# wa szA wb szB) s
+ where
+ szA = wordArraySize# wa
+ szB = wordArraySize# wb
+
+bignat_quot
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_quot mwq wa wb s =
+ ioVoid (c_mpn_tdiv_q mwq wa szA wb szB) s
+ where
+ szA = wordArraySize# wa
+ szB = wordArraySize# wb
+
+bignat_rem
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_rem mwr wa wb s =
+ ioVoid (c_mpn_tdiv_r mwr wa szA wb szB) s
+ where
+ szA = wordArraySize# wa
+ szB = wordArraySize# wb
+
+bignat_quotrem_word
+ :: MutableWordArray# RealWorld -- ^ Quotient
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> (# State# RealWorld, Word# #)
+bignat_quotrem_word mwq wa b s =
+ ioWord# (c_mpn_divrem_1 mwq 0# wa szA b) s
+ where
+ szA = wordArraySize# wa
+
+bignat_quot_word
+ :: MutableWordArray# RealWorld -- ^ Quotient
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_quot_word mwq wa b s =
+ case bignat_quotrem_word mwq wa b s of
+ (# s', _ #) -> s'
+
+bignat_rem_word
+ :: WordArray#
+ -> Word#
+ -> Word#
+bignat_rem_word wa b =
+ c_mpn_mod_1 wa (wordArraySize# wa) b
+
+
+bignat_gcd
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_gcd mwr wa wb s =
+ -- wa > wb
+ case ioInt# (c_mpn_gcd# mwr wa (wordArraySize# wa) wb (wordArraySize# wb)) s of
+ (# s', sz #) -> mwaSetSize# mwr (narrowGmpSize# sz) s'
+
+bignat_gcd_word
+ :: WordArray#
+ -> Word#
+ -> Word#
+bignat_gcd_word wa b = c_mpn_gcd_1# wa (wordArraySize# wa) b
+
+bignat_gcd_word_word
+ :: Word#
+ -> Word#
+ -> Word#
+bignat_gcd_word_word = integer_gmp_gcd_word
+
+
+bignat_encode_double :: WordArray# -> Int# -> Double#
+bignat_encode_double wa e = c_mpn_get_d wa (wordArraySize# wa) e
+
+bignat_shiftr_neg
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_shiftr_neg mwa wa n s =
+ ioVoid (c_mpn_rshift_2c mwa wa (wordArraySize# wa) n) s
+
+bignat_powmod_word
+ :: WordArray#
+ -> WordArray#
+ -> Word#
+ -> Word#
+bignat_powmod_word b e m =
+ integer_gmp_powm1# b (wordArraySize# b) e (wordArraySize# e) m
+
+bignat_powmod_words
+ :: Word#
+ -> Word#
+ -> Word#
+ -> Word#
+bignat_powmod_words = integer_gmp_powm_word
+
+bignat_powmod
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_powmod r b e m s =
+ ioVoid (integer_gmp_powm# r b (wordArraySize# b) e (wordArraySize# e) m (wordArraySize# m)) s
+
+
+----------------------------------------------------------------------
+-- FFI ccall imports
+
+foreign import ccall unsafe "integer_gmp_gcd_word"
+ integer_gmp_gcd_word :: GmpLimb# -> GmpLimb# -> GmpLimb#
+
+foreign import ccall unsafe "integer_gmp_mpn_gcd_1"
+ c_mpn_gcd_1# :: ByteArray# -> GmpSize# -> GmpLimb# -> GmpLimb#
+
+foreign import ccall unsafe "integer_gmp_mpn_gcd"
+ c_mpn_gcd# :: MutableByteArray# s -> ByteArray# -> GmpSize#
+ -> ByteArray# -> GmpSize# -> IO GmpSize
+
+foreign import ccall unsafe "integer_gmp_gcdext"
+ integer_gmp_gcdext# :: MutableByteArray# s -> MutableByteArray# s
+ -> ByteArray# -> GmpSize#
+ -> ByteArray# -> GmpSize# -> IO GmpSize
+
+-- mp_limb_t mpn_add_1 (mp_limb_t *rp, const mp_limb_t *s1p, mp_size_t n,
+-- mp_limb_t s2limb)
+foreign import ccall unsafe "gmp.h __gmpn_add_1"
+ c_mpn_add_1 :: MutableByteArray# s -> ByteArray# -> GmpSize# -> GmpLimb#
+ -> IO GmpLimb
+
+-- mp_limb_t mpn_sub_1 (mp_limb_t *rp, const mp_limb_t *s1p, mp_size_t n,
+-- mp_limb_t s2limb)
+foreign import ccall unsafe "gmp.h __gmpn_sub_1"
+ c_mpn_sub_1 :: MutableByteArray# s -> ByteArray# -> GmpSize# -> GmpLimb#
+ -> IO GmpLimb
+
+-- mp_limb_t mpn_mul_1 (mp_limb_t *rp, const mp_limb_t *s1p, mp_size_t n,
+-- mp_limb_t s2limb)
+foreign import ccall unsafe "gmp.h __gmpn_mul_1"
+ c_mpn_mul_1 :: MutableByteArray# s -> ByteArray# -> GmpSize# -> GmpLimb#
+ -> IO GmpLimb
+
+-- mp_limb_t mpn_add (mp_limb_t *rp, const mp_limb_t *s1p, mp_size_t s1n,
+-- const mp_limb_t *s2p, mp_size_t s2n)
+foreign import ccall unsafe "gmp.h __gmpn_add"
+ c_mpn_add :: MutableByteArray# s -> ByteArray# -> GmpSize#
+ -> ByteArray# -> GmpSize# -> IO GmpLimb
+
+-- mp_limb_t mpn_sub (mp_limb_t *rp, const mp_limb_t *s1p, mp_size_t s1n,
+-- const mp_limb_t *s2p, mp_size_t s2n)
+foreign import ccall unsafe "gmp.h __gmpn_sub"
+ c_mpn_sub :: MutableByteArray# s -> ByteArray# -> GmpSize# -> ByteArray#
+ -> GmpSize# -> IO GmpLimb
+
+-- mp_limb_t mpn_mul (mp_limb_t *rp, const mp_limb_t *s1p, mp_size_t s1n,
+-- const mp_limb_t *s2p, mp_size_t s2n)
+foreign import ccall unsafe "gmp.h __gmpn_mul"
+ c_mpn_mul :: MutableByteArray# s -> ByteArray# -> GmpSize# -> ByteArray#
+ -> GmpSize# -> IO GmpLimb
+
+-- int mpn_cmp (const mp_limb_t *s1p, const mp_limb_t *s2p, mp_size_t n)
+foreign import ccall unsafe "gmp.h __gmpn_cmp"
+ c_mpn_cmp :: ByteArray# -> ByteArray# -> GmpSize# -> Int#
+
+-- void mpn_tdiv_qr (mp_limb_t *qp, mp_limb_t *rp, mp_size_t qxn,
+-- const mp_limb_t *np, mp_size_t nn,
+-- const mp_limb_t *dp, mp_size_t dn)
+foreign import ccall unsafe "gmp.h __gmpn_tdiv_qr"
+ c_mpn_tdiv_qr :: MutableByteArray# s -> MutableByteArray# s -> GmpSize#
+ -> ByteArray# -> GmpSize# -> ByteArray# -> GmpSize# -> IO ()
+
+foreign import ccall unsafe "integer_gmp_mpn_tdiv_q"
+ c_mpn_tdiv_q :: MutableByteArray# s -> ByteArray# -> GmpSize# -> ByteArray#
+ -> GmpSize# -> IO ()
+
+foreign import ccall unsafe "integer_gmp_mpn_tdiv_r"
+ c_mpn_tdiv_r :: MutableByteArray# s -> ByteArray# -> GmpSize# -> ByteArray#
+ -> GmpSize# -> IO ()
+
+-- mp_limb_t mpn_divrem_1 (mp_limb_t *r1p, mp_size_t qxn, mp_limb_t *s2p,
+-- mp_size_t s2n, mp_limb_t s3limb)
+foreign import ccall unsafe "gmp.h __gmpn_divrem_1"
+ c_mpn_divrem_1 :: MutableByteArray# s -> GmpSize# -> ByteArray# -> GmpSize#
+ -> GmpLimb# -> IO GmpLimb
+
+-- mp_limb_t mpn_mod_1 (const mp_limb_t *s1p, mp_size_t s1n, mp_limb_t s2limb)
+foreign import ccall unsafe "gmp.h __gmpn_mod_1"
+ c_mpn_mod_1 :: ByteArray# -> GmpSize# -> GmpLimb# -> GmpLimb#
+
+-- mp_limb_t integer_gmp_mpn_rshift (mp_limb_t rp[], const mp_limb_t sp[],
+-- mp_size_t sn, mp_bitcnt_t count)
+foreign import ccall unsafe "integer_gmp_mpn_rshift"
+ c_mpn_rshift :: MutableByteArray# s -> ByteArray# -> GmpSize# -> Word#
+ -> IO GmpLimb
+
+-- mp_limb_t integer_gmp_mpn_rshift (mp_limb_t rp[], const mp_limb_t sp[],
+-- mp_size_t sn, mp_bitcnt_t count)
+foreign import ccall unsafe "integer_gmp_mpn_rshift_2c"
+ c_mpn_rshift_2c :: MutableByteArray# s -> ByteArray# -> GmpSize# -> Word#
+ -> IO GmpLimb
+
+-- mp_limb_t integer_gmp_mpn_lshift (mp_limb_t rp[], const mp_limb_t sp[],
+-- mp_size_t sn, mp_bitcnt_t count)
+foreign import ccall unsafe "integer_gmp_mpn_lshift"
+ c_mpn_lshift :: MutableByteArray# s -> ByteArray# -> GmpSize# -> Word#
+ -> IO GmpLimb
+
+-- void mpn_and_n (mp_limb_t *rp, const mp_limb_t *s1p, const mp_limb_t *s2p,
+-- mp_size_t n)
+foreign import ccall unsafe "integer_gmp_mpn_and_n"
+ c_mpn_and_n :: MutableByteArray# s -> ByteArray# -> ByteArray# -> GmpSize#
+ -> IO ()
+
+-- void mpn_andn_n (mp_limb_t *rp, const mp_limb_t *s1p, const mp_limb_t *s2p,
+-- mp_size_t n)
+foreign import ccall unsafe "integer_gmp_mpn_andn_n"
+ c_mpn_andn_n :: MutableByteArray# s -> ByteArray# -> ByteArray# -> GmpSize#
+ -> IO ()
+
+-- void mpn_ior_n (mp_limb_t *rp, const mp_limb_t *s1p, const mp_limb_t *s2p,
+-- mp_size_t n)
+foreign import ccall unsafe "integer_gmp_mpn_ior_n"
+ c_mpn_ior_n :: MutableByteArray# s -> ByteArray# -> ByteArray# -> GmpSize#
+ -> IO ()
+
+-- void mpn_xor_n (mp_limb_t *rp, const mp_limb_t *s1p, const mp_limb_t *s2p,
+-- mp_size_t n)
+foreign import ccall unsafe "integer_gmp_mpn_xor_n"
+ c_mpn_xor_n :: MutableByteArray# s -> ByteArray# -> ByteArray# -> GmpSize#
+ -> IO ()
+
+-- mp_bitcnt_t mpn_popcount (const mp_limb_t *s1p, mp_size_t n)
+foreign import ccall unsafe "gmp.h __gmpn_popcount"
+ c_mpn_popcount :: ByteArray# -> GmpSize# -> Word#
+
+-- double integer_gmp_mpn_get_d (const mp_limb_t sp[], const mp_size_t sn)
+foreign import ccall unsafe "integer_gmp_mpn_get_d"
+ c_mpn_get_d :: ByteArray# -> GmpSize# -> Int# -> Double#
+
+foreign import ccall unsafe "integer_gmp_powm"
+ integer_gmp_powm# :: MutableByteArray# RealWorld
+ -> ByteArray# -> GmpSize# -> ByteArray# -> GmpSize#
+ -> ByteArray# -> GmpSize# -> IO GmpSize
+
+foreign import ccall unsafe "integer_gmp_powm_word"
+ integer_gmp_powm_word :: GmpLimb# -> GmpLimb# -> GmpLimb# -> GmpLimb#
+
+foreign import ccall unsafe "integer_gmp_powm1"
+ integer_gmp_powm1# :: ByteArray# -> GmpSize# -> ByteArray# -> GmpSize#
+ -> GmpLimb# -> GmpLimb#
diff --git a/libraries/ghc-bignum/src/GHC/Num/BigNat/Native.hs b/libraries/ghc-bignum/src/GHC/Num/BigNat/Native.hs
new file mode 100644
index 0000000000..a25b36eaec
--- /dev/null
+++ b/libraries/ghc-bignum/src/GHC/Num/BigNat/Native.hs
@@ -0,0 +1,719 @@
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE NegativeLiterals #-}
+{-# LANGUAGE MultiWayIf #-}
+{-# LANGUAGE BinaryLiterals #-}
+{-# OPTIONS_GHC -Wno-name-shadowing #-}
+
+module GHC.Num.BigNat.Native where
+
+#include "MachDeps.h"
+#include "WordSize.h"
+
+#if defined(BIGNUM_NATIVE) || defined(BIGNUM_CHECK)
+import {-# SOURCE #-} GHC.Num.BigNat
+import {-# SOURCE #-} GHC.Num.Natural
+#else
+import GHC.Num.BigNat
+import GHC.Num.Natural
+#endif
+import GHC.Num.WordArray
+import GHC.Num.Primitives
+import GHC.Prim
+import GHC.Types
+
+default ()
+
+count_words_bits :: Word# -> (# Word#, Word# #)
+count_words_bits n = (# nw, nb #)
+ where
+ nw = n `uncheckedShiftRL#` WORD_SIZE_BITS_SHIFT#
+ nb = n `and#` WORD_SIZE_BITS_MASK##
+
+count_words_bits_int :: Word# -> (# Int#, Int# #)
+count_words_bits_int n = case count_words_bits n of
+ (# nw, nb #) -> (# word2Int# nw, word2Int# nb #)
+
+bignat_compare :: WordArray# -> WordArray# -> Int#
+bignat_compare wa wb = go (sz -# 1#)
+ where
+ sz = wordArraySize# wa
+ go i
+ | isTrue# (i <# 0#) = 0#
+ | a <- indexWordArray# wa i
+ , b <- indexWordArray# wb i
+ = if | isTrue# (a `eqWord#` b) -> go (i -# 1#)
+ | isTrue# (a `gtWord#` b) -> 1#
+ | True -> -1#
+
+bignat_add
+ :: MutableWordArray# s -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# s
+ -> State# s
+bignat_add mwa wa wb = addABc 0# 0##
+ where
+ !szA = wordArraySize# wa
+ !szB = wordArraySize# wb
+ !szMin = minI# szA szB
+
+ -- we have four cases:
+ -- 1) we have a digit in A and in B + a potential carry
+ -- => perform triple addition
+ -- => result in (carry,word)
+ -- 2) we have a digit only in A or B and a carry
+ -- => perform double addition from a single array
+ -- => result in (carry,word)
+ -- 3) we have a digit only in A or B and no carry
+ -- => perform array copy and shrink the array
+ -- 4) We only have a potential carry
+ -- => write the carry or shrink the array
+
+ addABc i carry s
+ | isTrue# (i <# szMin) =
+ let
+ !(# carry', r #) = plusWord3#
+ (indexWordArray# wa i)
+ (indexWordArray# wb i)
+ carry
+ in case mwaWrite# mwa i r s of
+ s' -> addABc (i +# 1#) carry' s'
+
+ | isTrue# ((i ==# szA) &&# (i ==# szB))
+ = mwaWriteOrShrink mwa carry i s
+
+ | isTrue# (i ==# szA)
+ = addAoBc wb i carry s
+
+ | True
+ = addAoBc wa i carry s
+
+ addAoBc wab i carry s
+ | isTrue# (i ==# wordArraySize# wab)
+ = mwaWriteOrShrink mwa carry i s
+
+ | 0## <- carry
+ = -- copy the remaining words and remove the word allocated for the
+ -- potential carry
+ case mwaArrayCopy# mwa i wab i (wordArraySize# wab -# i) s of
+ s' -> mwaShrink# mwa 1# s'
+
+ | True
+ = let !(# carry', r #) = plusWord2# (indexWordArray# wab i) carry
+ in case mwaWrite# mwa i r s of
+ s' -> addAoBc wab (i +# 1#) carry' s'
+
+bignat_add_word
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_add_word mwa wa b s = mwaInitArrayPlusWord mwa wa b s
+
+bignat_sub_word
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> (# State# RealWorld, Bool# #)
+bignat_sub_word mwa wa b = go b 0#
+ where
+ !sz = wordArraySize# wa
+ go carry i s
+ | isTrue# (i >=# sz)
+ = (# s, carry `neWord#` 0## #)
+
+ | 0## <- carry
+ = case mwaArrayCopy# mwa i wa i (sz -# i) s of
+ s' -> (# s', 0# #)
+
+ | True
+ = case subWordC# (indexWordArray# wa i) carry of
+ (# 0##, 0# #)
+ | isTrue# (i ==# sz) -> case mwaShrink# mwa 1# s of
+ s' -> (# s', 0# #)
+
+ (# l , c #) -> case mwaWrite# mwa i l s of
+ s1 -> go (int2Word# c) (i +# 1#) s1
+
+bignat_mul_word
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> Word#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_mul_word mwa wa b = go 0# 0##
+ where
+ !szA = wordArraySize# wa
+ go i carry s
+ | isTrue# (i ==# szA) = mwaWriteOrShrink mwa carry i s
+ | True =
+ let
+ ai = indexWordArray# wa i
+ !(# carry', r #) = plusWord12# carry (timesWord2# ai b)
+ in case mwaWrite# mwa i r s of
+ s' -> go (i +# 1#) carry' s'
+
+
+bignat_mul
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_mul mwa wa wb s1 =
+ -- initialize the resulting WordArray
+ case mwaFill# mwa 0## 0## (int2Word# sz) s1 of
+ s' -> mulEachB ctzB s' -- loop on b Words
+ where
+ !szA = wordArraySize# wa
+ !szB = wordArraySize# wb
+ !sz = szA +# szB
+
+ !ctzA = word2Int# (bigNatCtzWord# wa)
+ !ctzB = word2Int# (bigNatCtzWord# wb)
+
+ -- multiply a single bj Word# to the whole wa WordArray
+ mul bj j i carry s
+ | isTrue# (i ==# szA)
+ -- write the carry
+ = mwaAddInplaceWord# mwa (i +# j) carry s
+
+ | True = let
+ ai = indexWordArray# wa i
+ !(# c',r' #) = timesWord2# ai bj
+ !(# c'',r #) = plusWord2# r' carry
+ carry' = plusWord# c' c''
+ in case mwaAddInplaceWord# mwa (i +# j) r s of
+ s' -> mul bj j (i +# 1#) carry' s'
+
+ -- for each bj in wb, call `mul bj wa`
+ mulEachB i s
+ | isTrue# (i ==# szB) = s
+ | True = case indexWordArray# wb i of
+ -- detect bj == 0## and skip the loop
+ 0## -> mulEachB (i +# 1#) s
+ bi -> case mul bi i ctzA 0## s of
+ s' -> mulEachB (i +# 1#) s'
+
+bignat_sub
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> (# State# RealWorld, Bool# #)
+bignat_sub mwa wa wb s =
+ -- initialize the resulting WordArray
+ -- Note: we could avoid the copy by subtracting the first non-zero
+ -- less-significant word of b...
+ case mwaArrayCopy# mwa 0# wa 0# (wordArraySize# wa) s of
+ s' -> mwaSubInplaceArray mwa 0# wb s'
+
+bignat_popcount :: WordArray# -> Word#
+bignat_popcount wa = go 0# 0##
+ where
+ !sz = wordArraySize# wa
+ go i c
+ | isTrue# (i ==# sz) = c
+ | True = go (i +# 1#) (c `plusWord#` popCnt# (indexWordArray# wa i))
+
+bignat_shiftl
+ :: MutableWordArray# s
+ -> WordArray#
+ -> Word#
+ -> State# s
+ -> State# s
+bignat_shiftl mwa wa n s1 =
+ -- set the lower words to 0
+ case mwaFill# mwa 0## 0## (int2Word# nw) s1 of
+ s2 -> if
+ | 0# <- nb -> mwaArrayCopy# mwa nw wa 0# szA s2
+ | True -> mwaBitShift 0# 0## s2
+ where
+ !szA = wordArraySize# wa
+ !(# nw, nb #) = count_words_bits_int n
+ !sh = WORD_SIZE_IN_BITS# -# nb
+
+ -- Bit granularity (c is the carry from the previous shift)
+ mwaBitShift i c s
+ -- write the carry
+ | isTrue# (i ==# szA)
+ = mwaWriteOrShrink mwa c (i +# nw) s
+
+ | True =
+ let
+ !ai = indexWordArray# wa i
+ !v = c `or#` (ai `uncheckedShiftL#` nb)
+ !c' = ai `uncheckedShiftRL#` sh
+ in case mwaWrite# mwa (i +# nw) v s of
+ s' -> mwaBitShift (i +# 1#) c' s'
+
+
+bignat_shiftr
+ :: MutableWordArray# s
+ -> WordArray#
+ -> Word#
+ -> State# s
+ -> State# s
+bignat_shiftr mwa wa n s1
+ | isTrue# (nb ==# 0#) = mwaArrayCopy# mwa 0# wa nw sz s1
+ | True = mwaBitShift (sz -# 1#) 0## s1
+ where
+ !szA = wordArraySize# wa
+ !(# nw, nb #) = count_words_bits_int n
+ !sz = szA -# nw
+ !sh = WORD_SIZE_IN_BITS# -# nb
+
+ -- Bit granularity (c is the carry from the previous shift)
+ mwaBitShift i c s
+ | isTrue# (i <# 0#) = s
+ | True =
+ let
+ !ai = indexWordArray# wa (i +# nw)
+ !v = c `or#` (ai `uncheckedShiftRL#` nb)
+ !c' = ai `uncheckedShiftL#` sh
+ in case mwaWrite# mwa i v s of
+ s' -> mwaBitShift (i -# 1#) c' s'
+
+bignat_shiftr_neg
+ :: MutableWordArray# s
+ -> WordArray#
+ -> Word#
+ -> State# s
+ -> State# s
+bignat_shiftr_neg mwa wa n s1
+ -- initialize higher limb
+ = case mwaWrite# mwa (szA -# 1#) 0## s1 of
+ s2 -> case bignat_shiftr mwa wa n s2 of
+ s3 -> if nz_shifted_out
+ -- round if non-zero bits were shifted out
+ then mwaAddInplaceWord# mwa 0# 1## s3
+ else s3
+ where
+ !szA = wordArraySize# wa
+ !(# nw, nb #) = count_words_bits_int n
+
+ -- non-zero bits are shifted out?
+ nz_shifted_out
+ -- test nb bits
+ | isTrue# (
+ (nb /=# 0#)
+ &&# (indexWordArray# wa nw `uncheckedShiftL#`
+ (WORD_SIZE_IN_BITS# -# nb) `neWord#` 0##))
+ = True
+ -- test nw words
+ | True
+ = let
+ go j
+ | isTrue# (j ==# nw) = False
+ | isTrue# (indexWordArray# wa j `neWord#` 0##) = True
+ | True = go (j +# 1#)
+ in go 0#
+
+
+bignat_or
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_or mwa wa wb s1
+ | isTrue# (szA >=# szB) = go wa szA wb szB s1
+ | True = go wb szB wa szA s1
+ where
+ !szA = wordArraySize# wa
+ !szB = wordArraySize# wb
+ -- nx >= ny
+ go wx nx wy ny s =
+ case mwaInitArrayBinOp mwa wx wy or# s of
+ s' -> mwaArrayCopy# mwa ny wx ny (nx -# ny) s'
+
+bignat_xor
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_xor mwa wa wb s1
+ | isTrue# (szA >=# szB) = go wa szA wb szB s1
+ | True = go wb szB wa szA s1
+ where
+ !szA = wordArraySize# wa
+ !szB = wordArraySize# wb
+ -- nx >= ny
+ go wx nx wy ny s =
+ case mwaInitArrayBinOp mwa wx wy xor# s of
+ s' -> mwaArrayCopy# mwa ny wx ny (nx -# ny) s'
+
+bignat_and
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_and mwa wa wb s = mwaInitArrayBinOp mwa wa wb and# s
+
+bignat_and_not
+ :: MutableWordArray# RealWorld -- ^ Result
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_and_not mwa wa wb s =
+ case mwaInitArrayBinOp mwa wa wb (\x y -> x `and#` not# y) s of
+ s' -> mwaArrayCopy# mwa szB wa szB (szA -# szB) s'
+ where
+ !szA = wordArraySize# wa
+ !szB = wordArraySize# wb
+
+bignat_quotrem
+ :: MutableWordArray# s
+ -> MutableWordArray# s
+ -> WordArray#
+ -> WordArray#
+ -> State# s
+ -> State# s
+bignat_quotrem mwq mwr uwa uwb s0 =
+ -- Normalization consists in left-shifting bits in B and A so that the
+ -- most-significant bit of the most-significant word of B is 1. It makes
+ -- quotient prediction much more efficient as we only use the two most
+ -- significant words of A and the most significant word of B to make the
+ -- prediction.
+
+ -- we will left-shift A and B of "clzb" bits for normalization
+ let !clzb = clz# (indexWordArray# uwb (wordArraySize# uwb -# 1#))
+
+ -- we use a single array initially containing A (normalized) and
+ -- returning the remainder (normalized): mnwa (for "mutable normalized
+ -- wordarray A")
+ --
+ -- We allocate it here with an additionnal Word compared to A because
+ -- normalizing can left shift at most (N-1) bits (on N-bit arch).
+ in case newWordArray# (wordArraySize# uwa +# 1#) s0 of { (# s1, mnwa #) ->
+
+ -- normalized A in mnwa
+ let normalizeA s = case mwaWrite# mnwa (wordArraySize# uwa) 0## s of -- init potential carry
+ s -> case bignat_shiftl mnwa uwa clzb s of -- left shift
+ s -> mwaTrimZeroes# mnwa s -- remove null carry if any
+ in case normalizeA s1 of { s2 ->
+
+ -- normalize B. We don't do it in a MutableWordArray because it will remain
+ -- constant during the whole computation.
+ let !nwb = bigNatShiftL# uwb clzb in
+
+ -- perform quotrem on normalized inputs
+ case bignat_quotrem_normalized mwq mnwa nwb s2 of { s3 ->
+
+ -- denormalize the remainder now stored in mnwa. We just have to right shift
+ -- of "clzb" bits. We copy the result into "mwr" array.
+ let denormalizeR s = case mwaTrimZeroes# mnwa s of
+ s -> case unsafeFreezeByteArray# mnwa s of
+ (# s, wr #) -> case mwaSetSize# mwr (wordArraySize# wr) s of
+ s -> case bignat_shiftr mwr wr clzb s of
+ s -> mwaTrimZeroes# mwr s
+ in denormalizeR s3
+ }}}
+
+
+
+bignat_quot
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_quot mwq wa wb s =
+ -- allocate a temporary array for the remainder and call quotrem
+ case newWordArray# (wordArraySize# wb) s of
+ (# s, mwr #) -> bignat_quotrem mwq mwr wa wb s
+
+bignat_rem
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_rem mwr wa wb s =
+ -- allocate a temporary array for the quotient and call quotrem
+ -- (we could avoid allocating it as it is not used to compute the result but
+ -- it would require non trivial modification of bignat_quotrem)
+ case newWordArray# szQ s of
+ (# s, mwq #) -> bignat_quotrem mwq mwr wa wb s
+ where
+ szA = wordArraySize# wa
+ szB = wordArraySize# wb
+ szQ = 1# +# szA -# szB
+
+-- | Perform quotRem on normalized inputs:
+-- * highest bit of B is set
+-- * A is trimmed
+-- * A >= B
+-- * B > 1
+bignat_quotrem_normalized
+ :: MutableWordArray# s
+ -> MutableWordArray# s
+ -> WordArray#
+ -> State# s
+ -> State# s
+bignat_quotrem_normalized mwq mwa b s0 =
+
+ -- n is the size of B
+ let !n = wordArraySize# b
+
+ -- m+n is the size of A (m >= 0)
+ in case mwaSize# mwa s0 of { (# s1, szA #) ->
+ let !m = szA -# n in
+
+ -- Definitions:
+ -- MSW(x) is the most-significant word of x
+ -- MSB(x) the most-significant bit of x
+
+ -- We first compute MSW(Q). Thanks to the normalization of B, MSW(Q) can
+ -- only be 0 or 1 so we only have to perform a prefix comparison to compute
+ -- MSW(Q).
+ --
+ -- Proof MSW(Q) < 2:
+ -- * MSB(MSW(B)) = 1 thanks to normalization.
+ -- * MSW(B) * MSW(Q) <= MSW(A) by definition
+ -- * suppose MSW(Q) >= 2:
+ -- MSW(B) * MSW(Q) >= MSW(B) << 1 { MSW(Q) >= 2 }
+ -- > MAX_WORD_VALUE { MSB(MSW(B)) = 1 }
+ -- > MSW(A) { MSW(A) <= MAX_WORD_VALUE }
+ -- contradiction.
+ --
+ -- If A >= (B << m words)
+ -- then Qm = 1
+ -- A := A - (B << m words)
+ -- else Qm = 0
+ -- A unchanged
+ let computeQm s = case mwaTrimCompare m mwa b s of
+ (# s, LT #) -> (# s, 0## #)
+ (# s, _ #) -> (# s, 1## #)
+
+ updateQj j qj qjb s = case mwaWrite# mwq j qj s of -- write Qj
+ s | 0## <- qj -> s
+ | True -> case mwaSubInplaceArray mwa j qjb s of -- subtract (qjB << j words)
+ (# s, _ #) -> s
+
+ -- update the highest word of Q
+ updateQm s = case computeQm s of
+ (# s, qm #) -> updateQj m qm b s
+
+ -- the size of Q is szA+szB+1 BEFORE normalization. Normalization may add
+ -- an additional higher word to A.
+ -- * If A has an additional limb:
+ -- * MSW(A) < MSW(B). Because MSB(MSW(A)) can't be set (it would
+ -- mean that we shifted a whole word, which we didn't)
+ -- * hence MSW(Q) = 0 but we don't have to write it (and we mustn't)
+ -- because of the size of Q
+ -- * If A has no additional limb:
+ -- * We have to check if MSW(A) >= MSW(B) and to adjust A and MSW(Q)
+ -- accordingly
+ --
+ -- We detect if A has an additional limb by comparing the size of Q with m
+ updateQmMaybe s = case mwaSize# mwq s of
+ (# s, szQ #) | isTrue# (m <# szQ) -> updateQm s
+ | True -> s
+
+ in case updateQmMaybe s1 of { s2 ->
+
+
+ -- main loop: for j from (m-1) downto 0
+ -- We estimate a one Word quotient qj:
+ -- e1e0 <- a(n+j)a(n+j-1) `div` b(n-1)
+ -- qj | e1 == 0 = e0
+ -- | otherwise = maxBound
+ -- We loop until we find the real quotient:
+ -- while (A < ((qj*B) << j words)) qj--
+ -- We update A and Qj:
+ -- Qj := qj
+ -- A := A - (qj*B << j words)
+
+ let bmsw = wordArrayLast# b -- most significant word of B
+
+ estimateQj j s =
+ case mwaRead# mwa (n +# j) s of
+ (# s, a1 #) -> case mwaRead# mwa (n +# j -# 1#) s of
+ (# s, a0 #) -> case quotRemWord3# (# a1, a0 #) bmsw of
+ (# (# 0##, qj #), _ #) -> (# s, qj #)
+ (# (# _, _ #), _ #) -> (# s, WORD_MAXBOUND## #)
+
+ -- we perform the qj*B multiplication once and then we subtract B from
+ -- qj*B as much as needed until (qj'*B << j words) <= A
+ findRealQj j qj s = findRealQj' j qj (bigNatMulWord# b qj) s
+
+ findRealQj' j qj qjB s = case mwaTrimCompare j mwa qjB s of
+ (# s, LT #) -> findRealQj' j (qj `minusWord#` 1##) (bigNatSubUnsafe qjB b) s
+ -- TODO: we could do the sub inplace to
+ -- reduce allocations
+ (# s, _ #) -> (# s, qj, qjB #)
+
+ loop j s = case estimateQj j s of
+ (# s, qj #) -> case findRealQj j qj s of
+ (# s, qj, qjB #) -> case updateQj j qj qjB s of
+ s | 0# <- j -> s
+ | True -> loop (j -# 1#) s
+
+
+ in if | 0# <- m -> s2
+ | True -> loop (m -# 1#) s2
+ }}
+
+bignat_quotrem_word
+ :: MutableWordArray# s -- ^ Quotient
+ -> WordArray#
+ -> Word#
+ -> State# s
+ -> (# State# s, Word# #)
+bignat_quotrem_word mwq wa b s = go (sz -# 1#) 0## s
+ where
+ sz = wordArraySize# wa
+ go i r s
+ | isTrue# (i <# 0#) = (# s, r #)
+ | True =
+ let
+ ai = indexWordArray# wa i
+ !(# q,r' #) = quotRemWord2# r ai b
+ in case mwaWrite# mwq i q s of
+ s' -> go (i -# 1#) r' s'
+
+bignat_quot_word
+ :: MutableWordArray# s -- ^ Quotient
+ -> WordArray#
+ -> Word#
+ -> State# s
+ -> State# s
+bignat_quot_word mwq wa b s = go (sz -# 1#) 0## s
+ where
+ sz = wordArraySize# wa
+ go i r s
+ | isTrue# (i <# 0#) = s
+ | True =
+ let
+ ai = indexWordArray# wa i
+ !(# q,r' #) = quotRemWord2# r ai b
+ in case mwaWrite# mwq i q s of
+ s' -> go (i -# 1#) r' s'
+
+bignat_rem_word
+ :: WordArray#
+ -> Word#
+ -> Word#
+bignat_rem_word wa b = go (sz -# 1#) 0##
+ where
+ sz = wordArraySize# wa
+ go i r
+ | isTrue# (i <# 0#) = r
+ | True =
+ let
+ ai = indexWordArray# wa i
+ !(# _,r' #) = quotRemWord2# r ai b
+ in go (i -# 1#) r'
+
+
+bignat_gcd
+ :: MutableWordArray# s
+ -> WordArray#
+ -> WordArray#
+ -> State# s
+ -> State# s
+bignat_gcd mwr = go
+ where
+ go wmax wmin s
+ | isTrue# (wordArraySize# wmin ==# 0#)
+ = mwaInitCopyShrink# mwr wmax s
+
+ | True
+ = let
+ wmax' = wmin
+ !wmin' = bigNatRem wmax wmin
+ in go wmax' wmin' s
+
+bignat_gcd_word
+ :: WordArray#
+ -> Word#
+ -> Word#
+bignat_gcd_word a b = bignat_gcd_word_word b (bigNatRemWord# a b)
+
+-- | This operation doesn't really belongs here, but GMP's one is much faster
+-- than this simple implementation (basic Euclid algorithm).
+--
+-- Ideally we should make an implementation as fast as GMP's one and put it into
+-- GHC.Num.Primitives.
+bignat_gcd_word_word
+ :: Word#
+ -> Word#
+ -> Word#
+bignat_gcd_word_word a 0## = a
+bignat_gcd_word_word a b = bignat_gcd_word_word b (a `remWord#` b)
+
+bignat_encode_double :: WordArray# -> Int# -> Double#
+bignat_encode_double wa e0 = go 0.0## e0 0#
+ where
+ sz = wordArraySize# wa
+ go acc e i
+ | isTrue# (i >=# sz) = acc
+ | True
+ = go (acc +## wordEncodeDouble# (indexWordArray# wa i) e)
+ (e +# WORD_SIZE_IN_BITS#) -- FIXME: we assume that e doesn't overflow...
+ (i +# 1#)
+
+bignat_powmod_word :: WordArray# -> WordArray# -> Word# -> Word#
+bignat_powmod_word b0 e0 m = go (naturalFromBigNat b0) (naturalFromBigNat e0) (naturalFromWord# 1##)
+ where
+ go !b e !r
+ | isTrue# (e `naturalTestBit#` 0##)
+ = go b' e' ((r `naturalMul` b) `naturalRem` m')
+
+ | naturalIsZero e
+ = naturalToWord# r
+
+ | True
+ = go b' e' r
+ where
+ b' = (b `naturalMul` b) `naturalRem` m'
+ m' = naturalFromWord# m
+ e' = e `naturalShiftR#` 1## -- slightly faster than "e `div` 2"
+
+bignat_powmod
+ :: MutableWordArray# RealWorld
+ -> WordArray#
+ -> WordArray#
+ -> WordArray#
+ -> State# RealWorld
+ -> State# RealWorld
+bignat_powmod r b0 e0 m s = mwaInitCopyShrink# r r' s
+ where
+ !r' = go (naturalFromBigNat b0)
+ (naturalFromBigNat e0)
+ (naturalFromWord# 1##)
+
+ go !b e !r
+ | isTrue# (e `naturalTestBit#` 0##)
+ = go b' e' ((r `naturalMul` b) `naturalRem` m')
+
+ | naturalIsZero e
+ = naturalToBigNat r
+
+ | True
+ = go b' e' r
+ where
+ b' = (b `naturalMul` b) `naturalRem` m'
+ m' = naturalFromBigNat m
+ e' = e `naturalShiftR#` 1## -- slightly faster than "e `div` 2"
+
+bignat_powmod_words
+ :: Word#
+ -> Word#
+ -> Word#
+ -> Word#
+bignat_powmod_words b e m =
+ bignat_powmod_word (wordArrayFromWord# b)
+ (wordArrayFromWord# e)
+ m
diff --git a/libraries/ghc-bignum/src/GHC/Num/Integer.hs b/libraries/ghc-bignum/src/GHC/Num/Integer.hs
new file mode 100644
index 0000000000..b4f6ee0c54
--- /dev/null
+++ b/libraries/ghc-bignum/src/GHC/Num/Integer.hs
@@ -0,0 +1,1169 @@
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE NegativeLiterals #-}
+{-# LANGUAGE BinaryLiterals #-}
+{-# LANGUAGE BlockArguments #-}
+
+-- |
+-- Module : GHC.Num.Integer
+-- Copyright : (c) Sylvain Henry 2019,
+-- (c) Herbert Valerio Riedel 2014
+-- License : BSD3
+--
+-- Maintainer : sylvain@haskus.fr
+-- Stability : provisional
+-- Portability : non-portable (GHC Extensions)
+--
+-- The 'Integer' type.
+
+module GHC.Num.Integer where
+
+#include "MachDeps.h"
+#include "WordSize.h"
+
+import GHC.Prim
+import GHC.Types
+import GHC.Classes
+import GHC.Magic
+import GHC.Num.Primitives
+import GHC.Num.BigNat
+import GHC.Num.Natural
+
+#if WORD_SIZE_IN_BITS < 64
+import GHC.IntWord64
+#endif
+
+default ()
+
+-- | Arbitrary precision integers. In contrast with fixed-size integral types
+-- such as 'Int', the 'Integer' type represents the entire infinite range of
+-- integers.
+--
+-- Integers are stored in a kind of sign-magnitude form, hence do not expect
+-- two's complement form when using bit operations.
+--
+-- If the value is small (fit into an 'Int'), 'IS' constructor is used.
+-- Otherwise 'IP' and 'IN' constructors are used to store a 'BigNat'
+-- representing respectively the positive or the negative value magnitude.
+--
+-- Invariant: 'IP' and 'IN' are used iff value doesn't fit in 'IS'
+data Integer
+ = IS !Int# -- ^ iff value in @[minBound::'Int', maxBound::'Int']@ range
+ | IP !BigNat -- ^ iff value in @]maxBound::'Int', +inf[@ range
+ | IN !BigNat -- ^ iff value in @]-inf, minBound::'Int'[@ range
+
+
+-- | Check Integer invariants
+integerCheck# :: Integer -> Bool#
+integerCheck# (IS _) = 1#
+integerCheck# (IP bn) = bigNatCheck# bn &&# (bn `bigNatGtWord#` INT_MAXBOUND##)
+integerCheck# (IN bn) = bigNatCheck# bn &&# (bn `bigNatGtWord#` ABS_INT_MINBOUND##)
+
+-- | Check Integer invariants
+integerCheck :: Integer -> Bool
+integerCheck i = isTrue# (integerCheck# i)
+
+-- | Integer Zero
+integerZero :: Integer
+integerZero = IS 0#
+
+-- | Integer One
+integerOne :: Integer
+integerOne = IS 1#
+
+---------------------------------------------------------------------
+-- Conversions
+---------------------------------------------------------------------
+
+-- | Create a positive Integer from a BigNat
+integerFromBigNat :: BigNat -> Integer
+integerFromBigNat !bn
+ | bigNatIsZero bn
+ = integerZero
+
+ | isTrue# (bn `bigNatLeWord#` INT_MAXBOUND##)
+ = IS (word2Int# (bigNatIndex# bn 0#))
+
+ | True
+ = IP bn
+
+-- | Create a negative Integer from a BigNat
+integerFromBigNatNeg :: BigNat -> Integer
+integerFromBigNatNeg !bn
+ | bigNatIsZero bn
+ = integerZero
+
+ | 1# <- bigNatSize# bn
+ , i <- negateInt# (word2Int# (bigNatIndex# bn 0#))
+ , isTrue# (i <=# 0#)
+ = IS i
+
+ | True
+ = IN bn
+
+-- | Create an Integer from a sign-bit and a BigNat
+integerFromBigNatSign :: Int# -> BigNat -> Integer
+integerFromBigNatSign !sign !bn
+ | 0# <- sign
+ = integerFromBigNat bn
+
+ | True
+ = integerFromBigNatNeg bn
+
+-- | Convert an Integer into a BigNat.
+--
+-- Return 0 for negative Integers.
+integerToBigNatClamp :: Integer -> BigNat
+integerToBigNatClamp (IP x) = x
+integerToBigNatClamp (IS x)
+ | isTrue# (x >=# 0#) = bigNatFromWord# (int2Word# x)
+integerToBigNatClamp _ = bigNatZero void#
+
+-- | Create an Integer from an Int#
+integerFromInt# :: Int# -> Integer
+integerFromInt# i = IS i
+
+-- | Create an Integer from an Int
+integerFromInt :: Int -> Integer
+integerFromInt (I# i) = IS i
+
+-- | Truncates 'Integer' to least-significant 'Int#'
+integerToInt# :: Integer -> Int#
+{-# NOINLINE integerToInt# #-}
+integerToInt# (IS i) = i
+integerToInt# (IP b) = word2Int# (bigNatToWord# b)
+integerToInt# (IN b) = negateInt# (word2Int# (bigNatToWord# b))
+
+-- | Truncates 'Integer' to least-significant 'Int#'
+integerToInt :: Integer -> Int
+integerToInt i = I# (integerToInt# i)
+
+-- | Convert a Word# into an Integer
+integerFromWord# :: Word# -> Integer
+{-# NOINLINE integerFromWord# #-}
+integerFromWord# w
+ | i <- word2Int# w
+ , isTrue# (i >=# 0#)
+ = IS i
+
+ | True
+ = IP (bigNatFromWord# w)
+
+-- | Convert a Word into an Integer
+integerFromWord :: Word -> Integer
+integerFromWord (W# w) = integerFromWord# w
+
+-- | Create a negative Integer with the given Word magnitude
+integerFromWordNeg# :: Word# -> Integer
+integerFromWordNeg# w
+ | isTrue# (w `leWord#` ABS_INT_MINBOUND##)
+ = IS (negateInt# (word2Int# w))
+
+ | True
+ = IN (bigNatFromWord# w)
+
+-- | Create an Integer from a sign and a Word magnitude
+integerFromWordSign# :: Int# -> Word# -> Integer
+integerFromWordSign# 0# w = integerFromWord# w
+integerFromWordSign# _ w = integerFromWordNeg# w
+
+-- | Truncate an Integer into a Word
+integerToWord# :: Integer -> Word#
+{-# NOINLINE integerToWord# #-}
+integerToWord# (IS i) = int2Word# i
+integerToWord# (IP bn) = bigNatToWord# bn
+integerToWord# (IN bn) = int2Word# (negateInt# (word2Int# (bigNatToWord# bn)))
+
+-- | Truncate an Integer into a Word
+integerToWord :: Integer -> Word
+integerToWord !i = W# (integerToWord# i)
+
+-- | Convert a Natural into an Integer
+integerFromNatural :: Natural -> Integer
+{-# NOINLINE integerFromNatural #-}
+integerFromNatural (NS x) = integerFromWord# x
+integerFromNatural (NB x) = integerFromBigNat x
+
+-- | Convert a list of Word into an Integer
+integerFromWordList :: Bool -> [Word] -> Integer
+integerFromWordList True ws = integerFromBigNatNeg (bigNatFromWordList ws)
+integerFromWordList False ws = integerFromBigNat (bigNatFromWordList ws)
+
+-- | Convert a Integer into a Natural
+--
+-- Return 0 for negative Integers.
+integerToNaturalClamp :: Integer -> Natural
+{-# NOINLINE integerToNaturalClamp #-}
+integerToNaturalClamp (IS x)
+ | isTrue# (x <# 0#) = naturalZero
+ | True = naturalFromWord# (int2Word# x)
+integerToNaturalClamp (IP x) = naturalFromBigNat x
+integerToNaturalClamp (IN _) = naturalZero
+
+-- | Convert a Integer into a Natural
+--
+-- Return absolute value
+integerToNatural :: Integer -> Natural
+{-# NOINLINE integerToNatural #-}
+integerToNatural (IS x) = naturalFromWord# (wordFromAbsInt# x)
+integerToNatural (IP x) = naturalFromBigNat x
+integerToNatural (IN x) = naturalFromBigNat x
+
+---------------------------------------------------------------------
+-- Predicates
+---------------------------------------------------------------------
+
+-- | Negative predicate
+integerIsNegative# :: Integer -> Bool#
+integerIsNegative# (IS i#) = i# <# 0#
+integerIsNegative# (IP _) = 0#
+integerIsNegative# (IN _) = 1#
+
+-- | Negative predicate
+integerIsNegative :: Integer -> Bool
+integerIsNegative !i = isTrue# (integerIsNegative# i)
+
+-- | Zero predicate
+integerIsZero :: Integer -> Bool
+integerIsZero (IS 0#) = True
+integerIsZero _ = False
+
+-- | Not-equal predicate.
+integerNe :: Integer -> Integer -> Bool
+integerNe !x !y = isTrue# (integerNe# x y)
+
+-- | Equal predicate.
+integerEq :: Integer -> Integer -> Bool
+integerEq !x !y = isTrue# (integerEq# x y)
+
+-- | Lower-or-equal predicate.
+integerLe :: Integer -> Integer -> Bool
+integerLe !x !y = isTrue# (integerLe# x y)
+
+-- | Lower predicate.
+integerLt :: Integer -> Integer -> Bool
+integerLt !x !y = isTrue# (integerLt# x y)
+
+-- | Greater predicate.
+integerGt :: Integer -> Integer -> Bool
+integerGt !x !y = isTrue# (integerGt# x y)
+
+-- | Greater-or-equal predicate.
+integerGe :: Integer -> Integer -> Bool
+integerGe !x !y = isTrue# (integerGe# x y)
+
+-- | Equal predicate.
+integerEq# :: Integer -> Integer -> Bool#
+{-# NOINLINE integerEq# #-}
+integerEq# (IS x) (IS y) = x ==# y
+integerEq# (IN x) (IN y) = bigNatEq# x y
+integerEq# (IP x) (IP y) = bigNatEq# x y
+integerEq# _ _ = 0#
+
+-- | Not-equal predicate.
+integerNe# :: Integer -> Integer -> Bool#
+{-# NOINLINE integerNe# #-}
+integerNe# (IS x) (IS y) = x /=# y
+integerNe# (IN x) (IN y) = bigNatNe# x y
+integerNe# (IP x) (IP y) = bigNatNe# x y
+integerNe# _ _ = 1#
+
+-- | Greater predicate.
+integerGt# :: Integer -> Integer -> Bool#
+{-# NOINLINE integerGt# #-}
+integerGt# (IS x) (IS y) = x ># y
+integerGt# x y | GT <- integerCompare x y = 1#
+integerGt# _ _ = 0#
+
+-- | Lower-or-equal predicate.
+integerLe# :: Integer -> Integer -> Bool#
+{-# NOINLINE integerLe# #-}
+integerLe# (IS x) (IS y) = x <=# y
+integerLe# x y | GT <- integerCompare x y = 0#
+integerLe# _ _ = 1#
+
+-- | Lower predicate.
+integerLt# :: Integer -> Integer -> Bool#
+{-# NOINLINE integerLt# #-}
+integerLt# (IS x) (IS y) = x <# y
+integerLt# x y | LT <- integerCompare x y = 1#
+integerLt# _ _ = 0#
+
+-- | Greater-or-equal predicate.
+integerGe# :: Integer -> Integer -> Bool#
+{-# NOINLINE integerGe# #-}
+integerGe# (IS x) (IS y) = x >=# y
+integerGe# x y | LT <- integerCompare x y = 0#
+integerGe# _ _ = 1#
+
+instance Eq Integer where
+ (==) = integerEq
+ (/=) = integerNe
+
+-- | Compare two Integer
+integerCompare :: Integer -> Integer -> Ordering
+{-# NOINLINE integerCompare #-}
+integerCompare (IS x) (IS y) = compareInt# x y
+integerCompare (IP x) (IP y) = bigNatCompare x y
+integerCompare (IN x) (IN y) = bigNatCompare y x
+integerCompare (IS _) (IP _) = LT
+integerCompare (IS _) (IN _) = GT
+integerCompare (IP _) (IS _) = GT
+integerCompare (IN _) (IS _) = LT
+integerCompare (IP _) (IN _) = GT
+integerCompare (IN _) (IP _) = LT
+
+instance Ord Integer where
+ compare = integerCompare
+
+---------------------------------------------------------------------
+-- Operations
+---------------------------------------------------------------------
+
+-- | Subtract one 'Integer' from another.
+integerSub :: Integer -> Integer -> Integer
+{-# NOINLINE integerSub #-}
+integerSub !x (IS 0#) = x
+integerSub (IS x#) (IS y#)
+ = case subIntC# x# y# of
+ (# z#, 0# #) -> IS z#
+ (# 0#, _ #) -> IN (bigNatFromWord2# 1## 0##)
+ (# z#, _ #)
+ | isTrue# (z# ># 0#)
+ -> IN (bigNatFromWord# ( (int2Word# (negateInt# z#))))
+ | True
+ -> IP (bigNatFromWord# ( (int2Word# z#)))
+integerSub (IS x#) (IP y)
+ | isTrue# (x# >=# 0#)
+ = integerFromBigNatNeg (bigNatSubWordUnsafe# y (int2Word# x#))
+ | True
+ = IN (bigNatAddWord# y (int2Word# (negateInt# x#)))
+integerSub (IS x#) (IN y)
+ | isTrue# (x# >=# 0#)
+ = IP (bigNatAddWord# y (int2Word# x#))
+ | True
+ = integerFromBigNat (bigNatSubWordUnsafe# y (int2Word# (negateInt# x#)))
+integerSub (IP x) (IP y)
+ = case bigNatCompare x y of
+ LT -> integerFromBigNatNeg (bigNatSubUnsafe y x)
+ EQ -> IS 0#
+ GT -> integerFromBigNat (bigNatSubUnsafe x y)
+integerSub (IP x) (IN y) = IP (bigNatAdd x y)
+integerSub (IN x) (IP y) = IN (bigNatAdd x y)
+integerSub (IN x) (IN y)
+ = case bigNatCompare x y of
+ LT -> integerFromBigNat (bigNatSubUnsafe y x)
+ EQ -> IS 0#
+ GT -> integerFromBigNatNeg (bigNatSubUnsafe x y)
+integerSub (IP x) (IS y#)
+ | isTrue# (y# >=# 0#)
+ = integerFromBigNat (bigNatSubWordUnsafe# x (int2Word# y#))
+ | True
+ = IP (bigNatAddWord# x (int2Word# (negateInt# y#)))
+integerSub (IN x) (IS y#)
+ | isTrue# (y# >=# 0#)
+ = IN (bigNatAddWord# x (int2Word# y#))
+ | True
+ = integerFromBigNatNeg (bigNatSubWordUnsafe# x (int2Word# (negateInt# y#)))
+
+-- | Add two 'Integer's
+integerAdd :: Integer -> Integer -> Integer
+{-# NOINLINE integerAdd #-}
+integerAdd !x (IS 0#) = x
+integerAdd (IS 0#) y = y
+integerAdd (IS x#) (IS y#)
+ = case addIntC# x# y# of
+ (# z#, 0# #) -> IS z#
+ (# 0#, _ #) -> IN (bigNatFromWord2# 1## 0##) -- 2*minBound::Int
+ (# z#, _ #)
+ | isTrue# (z# ># 0#) -> IN (bigNatFromWord# ( (int2Word# (negateInt# z#))))
+ | True -> IP (bigNatFromWord# ( (int2Word# z#)))
+integerAdd y@(IS _) x = integerAdd x y
+integerAdd (IP x) (IP y) = IP (bigNatAdd x y)
+integerAdd (IN x) (IN y) = IN (bigNatAdd x y)
+integerAdd (IP x) (IS y#) -- edge-case: @(maxBound+1) + minBound == 0@
+ | isTrue# (y# >=# 0#) = IP (bigNatAddWord# x (int2Word# y#))
+ | True = integerFromBigNat (bigNatSubWordUnsafe# x (int2Word#
+ (negateInt# y#)))
+integerAdd (IN x) (IS y#) -- edge-case: @(minBound-1) + maxBound == -2@
+ | isTrue# (y# >=# 0#) = integerFromBigNatNeg (bigNatSubWordUnsafe# x (int2Word# y#))
+ | True = IN (bigNatAddWord# x (int2Word# (negateInt# y#)))
+integerAdd y@(IN _) x@(IP _) = integerAdd x y
+integerAdd (IP x) (IN y)
+ = case bigNatCompare x y of
+ LT -> integerFromBigNatNeg (bigNatSubUnsafe y x)
+ EQ -> IS 0#
+ GT -> integerFromBigNat (bigNatSubUnsafe x y)
+
+-- | Multiply two 'Integer's
+integerMul :: Integer -> Integer -> Integer
+{-# NOINLINE integerMul #-}
+integerMul !_ (IS 0#) = IS 0#
+integerMul (IS 0#) _ = IS 0#
+integerMul x (IS 1#) = x
+integerMul (IS 1#) y = y
+integerMul x (IS -1#) = integerNegate x
+integerMul (IS -1#) y = integerNegate y
+#if __GLASGOW_HASKELL__ < 809
+integerMul (IS x) (IS y) = case mulIntMayOflo# x y of
+ 0# -> IS (x *# y)
+ _ -> case (# isTrue# (x >=# 0#), isTrue# (y >=# 0#) #) of
+ (# False, False #) -> case timesWord2# (int2Word# (negateInt# x))
+ (int2Word# (negateInt# y)) of
+ (# 0##,l #) -> integerFromWord# l
+ (# h ,l #) -> IP (bigNatFromWord2# h l)
+
+ (# True, False #) -> case timesWord2# (int2Word# x)
+ (int2Word# (negateInt# y)) of
+ (# 0##,l #) -> integerFromWordNeg# l
+ (# h ,l #) -> IN (bigNatFromWord2# h l)
+
+ (# False, True #) -> case timesWord2# (int2Word# (negateInt# x))
+ (int2Word# y) of
+ (# 0##,l #) -> integerFromWordNeg# l
+ (# h ,l #) -> IN (bigNatFromWord2# h l)
+
+ (# True, True #) -> case timesWord2# (int2Word# x)
+ (int2Word# y) of
+ (# 0##,l #) -> integerFromWord# l
+ (# h ,l #) -> IP (bigNatFromWord2# h l)
+#else
+integerMul (IS x) (IS y) = case timesInt2# x y of
+ (# 0#, _h, l #) -> IS l
+ (# _ , h, l #)
+ | isTrue# (h >=# 0#)
+ -> IP (bigNatFromWord2# (int2Word# h) (int2Word# l))
+ | True
+ -> let
+ -- two's complement of a two-word negative Int:
+ -- l' = complement l + 1
+ -- h' = complement h + carry
+ !(# l',c #) = addWordC# (not# (int2Word# l)) 1##
+ !h' = int2Word# c `plusWord#` not# (int2Word# h)
+ in IN (bigNatFromWord2# h' l')
+#endif
+integerMul x@(IS _) y = integerMul y x
+integerMul (IP x) (IP y) = IP (bigNatMul x y)
+integerMul (IP x) (IN y) = IN (bigNatMul x y)
+integerMul (IP x) (IS y)
+ | isTrue# (y >=# 0#) = IP (bigNatMulWord# x (int2Word# y))
+ | True = IN (bigNatMulWord# x (int2Word# (negateInt# y)))
+integerMul (IN x) (IN y) = IP (bigNatMul x y)
+integerMul (IN x) (IP y) = IN (bigNatMul x y)
+integerMul (IN x) (IS y)
+ | isTrue# (y >=# 0#) = IN (bigNatMulWord# x (int2Word# y))
+ | True = IP (bigNatMulWord# x (int2Word# (negateInt# y)))
+
+-- | Negate 'Integer'.
+--
+-- One edge-case issue to take into account is that Int's range is not
+-- symmetric around 0. I.e. @minBound+maxBound = -1@
+--
+-- IP is used iff n > maxBound::Int
+-- IN is used iff n < minBound::Int
+integerNegate :: Integer -> Integer
+{-# NOINLINE integerNegate #-}
+integerNegate (IN b) = IP b
+integerNegate (IS INT_MINBOUND#) = IP (bigNatFromWord# ABS_INT_MINBOUND##)
+integerNegate (IS i) = IS (negateInt# i)
+integerNegate (IP b)
+ | isTrue# (bigNatEqWord# b ABS_INT_MINBOUND##) = IS INT_MINBOUND#
+ | True = IN b
+
+
+-- | Compute absolute value of an 'Integer'
+integerAbs :: Integer -> Integer
+{-# NOINLINE integerAbs #-}
+integerAbs (IN i) = IP i
+integerAbs n@(IP _) = n
+integerAbs n@(IS i)
+ | isTrue# (i >=# 0#) = n
+ | INT_MINBOUND# <- i = IP (bigNatFromWord# ABS_INT_MINBOUND##)
+ | True = IS (negateInt# i)
+
+
+-- | Return @-1@, @0@, and @1@ depending on whether argument is
+-- negative, zero, or positive, respectively
+integerSignum :: Integer -> Integer
+{-# NOINLINE integerSignum #-}
+integerSignum !j = IS (integerSignum# j)
+
+-- | Return @-1#@, @0#@, and @1#@ depending on whether argument is
+-- negative, zero, or positive, respectively
+integerSignum# :: Integer -> Int#
+{-# NOINLINE integerSignum# #-}
+integerSignum# (IN _) = -1#
+integerSignum# (IS i#) = sgnI# i#
+integerSignum# (IP _ ) = 1#
+
+-- | Count number of set bits. For negative arguments returns
+-- the negated population count of the absolute value.
+integerPopCount# :: Integer -> Int#
+{-# NOINLINE integerPopCount# #-}
+integerPopCount# (IS i)
+ | isTrue# (i >=# 0#) = word2Int# (popCntI# i)
+ | True = negateInt# (word2Int# (popCntI# (negateInt# i)))
+integerPopCount# (IP bn) = word2Int# (bigNatPopCount# bn)
+integerPopCount# (IN bn) = negateInt# (word2Int# (bigNatPopCount# bn))
+
+-- | Positive 'Integer' for which only /n/-th bit is set
+integerBit# :: Word# -> Integer
+{-# NOINLINE integerBit# #-}
+integerBit# i
+ | isTrue# (i `ltWord#` (WORD_SIZE_IN_BITS## `minusWord#` 1##))
+ = IS (uncheckedIShiftL# 1# (word2Int# i))
+
+ | True = IP (bigNatBit# i)
+
+-- | 'Integer' for which only /n/-th bit is set
+integerBit :: Word -> Integer
+integerBit (W# i) = integerBit# i
+
+-- | Test if /n/-th bit is set.
+--
+-- Fake 2's complement for negative values (might be slow)
+integerTestBit# :: Integer -> Word# -> Bool#
+{-# NOINLINE integerTestBit# #-}
+integerTestBit# (IS x) i
+ | isTrue# (i `ltWord#` WORD_SIZE_IN_BITS##)
+ = testBitI# x i
+ | True
+ = x <# 0#
+integerTestBit# (IP x) i = bigNatTestBit# x i
+integerTestBit# (IN x) i
+ | isTrue# (iw >=# n)
+ = 1#
+ -- if all the limbs j with j < iw are null, then we have to consider the
+ -- carry of the 2's complement convertion. Otherwise we just have to return
+ -- the inverse of the bit test
+ | allZ iw = testBitW# (xi `minusWord#` 1##) ib ==# 0#
+ | True = testBitW# xi ib ==# 0#
+ where
+ !xi = bigNatIndex# x iw
+ !n = bigNatSize# x
+ !iw = word2Int# (i `uncheckedShiftRL#` WORD_SIZE_BITS_SHIFT#)
+ !ib = i `and#` WORD_SIZE_BITS_MASK##
+
+ allZ 0# = True
+ allZ j | isTrue# (bigNatIndex# x (j -# 1#) `eqWord#` 0##) = allZ (j -# 1#)
+ | True = False
+
+-- | Test if /n/-th bit is set. For negative Integers it tests the n-th bit of
+-- the negated argument.
+--
+-- Fake 2's complement for negative values (might be slow)
+integerTestBit :: Integer -> Word -> Bool
+integerTestBit !i (W# n) = isTrue# (integerTestBit# i n)
+
+-- | Shift-right operation
+--
+-- Fake 2's complement for negative values (might be slow)
+integerShiftR# :: Integer -> Word# -> Integer
+{-# NOINLINE integerShiftR# #-}
+integerShiftR# !x 0## = x
+integerShiftR# (IS i) n = IS (iShiftRA# i (word2Int# n))
+ where
+ iShiftRA# a b
+ | isTrue# (b >=# WORD_SIZE_IN_BITS#) = (a <# 0#) *# (-1#)
+ | True = a `uncheckedIShiftRA#` b
+integerShiftR# (IP bn) n = integerFromBigNat (bigNatShiftR# bn n)
+integerShiftR# (IN bn) n =
+ case integerFromBigNatNeg (bigNatShiftRNeg# bn n) of
+ IS 0# -> IS -1#
+ r -> r
+
+-- | Shift-right operation
+--
+-- Fake 2's complement for negative values (might be slow)
+integerShiftR :: Integer -> Word -> Integer
+integerShiftR !x (W# w) = integerShiftR# x w
+
+-- | Shift-left operation
+integerShiftL# :: Integer -> Word# -> Integer
+{-# NOINLINE integerShiftL# #-}
+integerShiftL# !x 0## = x
+integerShiftL# (IS 0#) _ = IS 0#
+integerShiftL# (IS 1#) n = integerBit# n
+integerShiftL# (IS i) n
+ | isTrue# (i >=# 0#) = integerFromBigNat (bigNatShiftL# (bigNatFromWord# (int2Word# i)) n)
+ | True = integerFromBigNatNeg (bigNatShiftL# (bigNatFromWord# (int2Word# (negateInt# i))) n)
+integerShiftL# (IP bn) n = IP (bigNatShiftL# bn n)
+integerShiftL# (IN bn) n = IN (bigNatShiftL# bn n)
+
+-- | Shift-left operation
+--
+-- Remember that bits are stored in sign-magnitude form, hence the behavior of
+-- negative Integers is different from negative Int's behavior.
+integerShiftL :: Integer -> Word -> Integer
+integerShiftL !x (W# w) = integerShiftL# x w
+
+-- | Bitwise OR operation
+--
+-- Fake 2's complement for negative values (might be slow)
+integerOr :: Integer -> Integer -> Integer
+{-# NOINLINE integerOr #-}
+integerOr a b = case a of
+ IS 0# -> b
+ IS -1# -> IS -1#
+ IS x -> case b of
+ IS 0# -> a
+ IS -1# -> IS -1#
+ IS y -> IS (orI# x y)
+ IP y
+ | isTrue# (x >=# 0#) -> integerFromBigNat (bigNatOrWord# y (int2Word# x))
+ | True -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatAndNot -- use De Morgan's laws
+ (bigNatFromWord#
+ (int2Word# (negateInt# x) `minusWord#` 1##))
+ y)
+ 1##)
+ IN y
+ | isTrue# (x >=# 0#) -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatAndNotWord# -- use De Morgan's laws
+ (bigNatSubWordUnsafe# y 1##)
+ (int2Word# x))
+ 1##)
+ | True -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatAndWord# -- use De Morgan's laws
+ (bigNatSubWordUnsafe# y 1##)
+ (int2Word# (negateInt# x) `minusWord#` 1##))
+ 1##)
+ IP x -> case b of
+ IS _ -> integerOr b a
+ IP y -> integerFromBigNat (bigNatOr x y)
+ IN y -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatAndNot -- use De Morgan's laws
+ (bigNatSubWordUnsafe# y 1##)
+ x)
+ 1##)
+ IN x -> case b of
+ IS _ -> integerOr b a
+ IN y -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatAnd -- use De Morgan's laws
+ (bigNatSubWordUnsafe# x 1##)
+ (bigNatSubWordUnsafe# y 1##))
+ 1##)
+ IP y -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatAndNot -- use De Morgan's laws
+ (bigNatSubWordUnsafe# x 1##)
+ y)
+ 1##)
+
+
+-- | Bitwise XOR operation
+--
+-- Fake 2's complement for negative values (might be slow)
+integerXor :: Integer -> Integer -> Integer
+{-# NOINLINE integerXor #-}
+integerXor a b = case a of
+ IS 0# -> b
+ IS -1# -> integerComplement b
+ IS x -> case b of
+ IS 0# -> a
+ IS -1# -> integerComplement a
+ IS y -> IS (xorI# x y)
+ IP y
+ | isTrue# (x >=# 0#) -> integerFromBigNat (bigNatXorWord# y (int2Word# x))
+ | True -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatXorWord#
+ y
+ (int2Word# (negateInt# x) `minusWord#` 1##))
+ 1##)
+ IN y
+ | isTrue# (x >=# 0#) -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatXorWord#
+ (bigNatSubWordUnsafe# y 1##)
+ (int2Word# x))
+ 1##)
+ | True -> integerFromBigNat
+ (bigNatXorWord# -- xor (not x) (not y) = xor x y
+ (bigNatSubWordUnsafe# y 1##)
+ (int2Word# (negateInt# x) `minusWord#` 1##))
+ IP x -> case b of
+ IS _ -> integerXor b a
+ IP y -> integerFromBigNat (bigNatXor x y)
+ IN y -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatXor
+ x
+ (bigNatSubWordUnsafe# y 1##))
+ 1##)
+ IN x -> case b of
+ IS _ -> integerXor b a
+ IN y -> integerFromBigNat
+ (bigNatXor -- xor (not x) (not y) = xor x y
+ (bigNatSubWordUnsafe# x 1##)
+ (bigNatSubWordUnsafe# y 1##))
+ IP y -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatXor
+ y
+ (bigNatSubWordUnsafe# x 1##))
+ 1##)
+
+
+
+-- | Bitwise AND operation
+--
+-- Fake 2's complement for negative values (might be slow)
+integerAnd :: Integer -> Integer -> Integer
+{-# NOINLINE integerAnd #-}
+integerAnd a b = case a of
+ IS 0# -> IS 0#
+ IS -1# -> b
+ IS x -> case b of
+ IS 0# -> IS 0#
+ IS -1# -> a
+ IS y -> IS (andI# x y)
+ IP y -> integerFromBigNat (bigNatAndInt# y x)
+ IN y
+ | isTrue# (x >=# 0#) -> integerFromWord# (int2Word# x `andNot#` (indexWordArray# y 0# `minusWord#` 1##))
+ | True -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatOrWord# -- use De Morgan's laws
+ (bigNatSubWordUnsafe# y 1##)
+ (wordFromAbsInt# x `minusWord#` 1##))
+ 1##)
+ IP x -> case b of
+ IS _ -> integerAnd b a
+ IP y -> integerFromBigNat (bigNatAnd x y)
+ IN y -> integerFromBigNat (bigNatAndNot x (bigNatSubWordUnsafe# y 1##))
+ IN x -> case b of
+ IS _ -> integerAnd b a
+ IN y -> integerFromBigNatNeg
+ (bigNatAddWord#
+ (bigNatOr -- use De Morgan's laws
+ (bigNatSubWordUnsafe# x 1##)
+ (bigNatSubWordUnsafe# y 1##))
+ 1##)
+ IP y -> integerFromBigNat (bigNatAndNot y (bigNatSubWordUnsafe# x 1##))
+
+
+
+-- | Binary complement of the
+integerComplement :: Integer -> Integer
+{-# NOINLINE integerComplement #-}
+integerComplement (IS x) = IS (notI# x)
+integerComplement (IP x) = IN (bigNatAddWord# x 1##)
+integerComplement (IN x) = IP (bigNatSubWordUnsafe# x 1##)
+
+
+-- | Simultaneous 'integerQuot' and 'integerRem'.
+--
+-- Divisor must be non-zero otherwise the GHC runtime will terminate
+-- with a division-by-zero fault.
+integerQuotRem# :: Integer -> Integer -> (# Integer, Integer #)
+{-# NOINLINE integerQuotRem# #-}
+integerQuotRem# !n (IS 1#) = (# n, IS 0# #)
+integerQuotRem# !n (IS -1#) = let !q = integerNegate n in (# q, (IS 0#) #)
+integerQuotRem# !_ (IS 0#) = (# divByZero, divByZero #)
+integerQuotRem# (IS 0#) _ = (# IS 0#, IS 0# #)
+integerQuotRem# (IS n#) (IS d#) = case quotRemInt# n# d# of
+ (# q#, r# #) -> (# IS q#, IS r# #)
+integerQuotRem# (IP n) (IP d) = case bigNatQuotRem# n d of
+ (# q, r #) -> (# integerFromBigNat q, integerFromBigNat r #)
+integerQuotRem# (IP n) (IN d) = case bigNatQuotRem# n d of
+ (# q, r #) -> (# integerFromBigNatNeg q, integerFromBigNat r #)
+integerQuotRem# (IN n) (IN d) = case bigNatQuotRem# n d of
+ (# q, r #) -> (# integerFromBigNat q, integerFromBigNatNeg r #)
+integerQuotRem# (IN n) (IP d) = case bigNatQuotRem# n d of
+ (# q, r #) -> (# integerFromBigNatNeg q, integerFromBigNatNeg r #)
+integerQuotRem# (IP n) (IS d#)
+ | isTrue# (d# >=# 0#) = case bigNatQuotRemWord# n (int2Word# d#) of
+ (# q, r# #) -> (# integerFromBigNat q, integerFromWord# r# #)
+ | True = case bigNatQuotRemWord# n (int2Word# (negateInt# d#)) of
+ (# q, r# #) -> (# integerFromBigNatNeg q, integerFromWord# r# #)
+integerQuotRem# (IN n) (IS d#)
+ | isTrue# (d# >=# 0#) = case bigNatQuotRemWord# n (int2Word# d#) of
+ (# q, r# #) -> (# integerFromBigNatNeg q, integerFromWordNeg# r# #)
+ | True = case bigNatQuotRemWord# n (int2Word# (negateInt# d#)) of
+ (# q, r# #) -> (# integerFromBigNat q, integerFromWordNeg# r# #)
+integerQuotRem# n@(IS _) (IN _) = (# IS 0#, n #) -- since @n < d@
+integerQuotRem# n@(IS n#) (IP d) -- need to account for (IS minBound)
+ | isTrue# (n# ># 0#) = (# IS 0#, n #)
+ | isTrue# (bigNatGtWord# d (int2Word# (negateInt# n#))) = (# IS 0#, n #)
+ | True {- abs(n) == d -} = (# IS -1#, IS 0# #)
+
+-- | Simultaneous 'integerQuot' and 'integerRem'.
+--
+-- Divisor must be non-zero otherwise the GHC runtime will terminate
+-- with a division-by-zero fault.
+integerQuotRem :: Integer -> Integer -> (Integer, Integer)
+integerQuotRem !x !y = case integerQuotRem# x y of
+ (# q, r #) -> (q, r)
+
+
+integerQuot :: Integer -> Integer -> Integer
+{-# NOINLINE integerQuot #-}
+integerQuot !n (IS 1#) = n
+integerQuot !n (IS -1#) = integerNegate n
+integerQuot !_ (IS 0#) = divByZero
+integerQuot (IS 0#) _ = IS 0#
+integerQuot (IS n#) (IS d#) = IS (quotInt# n# d#)
+integerQuot (IP n) (IS d#)
+ | isTrue# (d# >=# 0#) = integerFromBigNat (bigNatQuotWord# n (int2Word# d#))
+ | True = integerFromBigNatNeg (bigNatQuotWord# n
+ (int2Word# (negateInt# d#)))
+integerQuot (IN n) (IS d#)
+ | isTrue# (d# >=# 0#) = integerFromBigNatNeg (bigNatQuotWord# n (int2Word# d#))
+ | True = integerFromBigNat (bigNatQuotWord# n
+ (int2Word# (negateInt# d#)))
+integerQuot (IP n) (IP d) = integerFromBigNat (bigNatQuot n d)
+integerQuot (IP n) (IN d) = integerFromBigNatNeg (bigNatQuot n d)
+integerQuot (IN n) (IP d) = integerFromBigNatNeg (bigNatQuot n d)
+integerQuot (IN n) (IN d) = integerFromBigNat (bigNatQuot n d)
+integerQuot n d = case integerQuotRem# n d of (# q, _ #) -> q
+
+integerRem :: Integer -> Integer -> Integer
+{-# NOINLINE integerRem #-}
+integerRem !_ (IS 1#) = IS 0#
+integerRem _ (IS -1#) = IS 0#
+integerRem _ (IS 0#) = IS (remInt# 0# 0#)
+integerRem (IS 0#) _ = IS 0#
+integerRem (IS n#) (IS d#) = IS (remInt# n# d#)
+integerRem (IP n) (IS d#)
+ = integerFromWord# (bigNatRemWord# n (int2Word# (absI# d#)))
+integerRem (IN n) (IS d#)
+ = integerFromWordNeg# (bigNatRemWord# n (int2Word# (absI# d#)))
+integerRem (IP n) (IP d) = integerFromBigNat (bigNatRem n d)
+integerRem (IP n) (IN d) = integerFromBigNat (bigNatRem n d)
+integerRem (IN n) (IP d) = integerFromBigNatNeg (bigNatRem n d)
+integerRem (IN n) (IN d) = integerFromBigNatNeg (bigNatRem n d)
+integerRem n d = case integerQuotRem# n d of (# _, r #) -> r
+
+
+-- | Simultaneous 'integerDiv' and 'integerMod'.
+--
+-- Divisor must be non-zero otherwise the GHC runtime will terminate
+-- with a division-by-zero fault.
+integerDivMod# :: Integer -> Integer -> (# Integer, Integer #)
+{-# NOINLINE integerDivMod# #-}
+integerDivMod# !n !d
+ | isTrue# (integerSignum# r ==# negateInt# (integerSignum# d))
+ = let !q' = integerAdd q (IS -1#) -- TODO: optimize
+ !r' = integerAdd r d
+ in (# q', r' #)
+ | True = qr
+ where
+ !qr@(# q, r #) = integerQuotRem# n d
+
+-- | Simultaneous 'integerDiv' and 'integerMod'.
+--
+-- Divisor must be non-zero otherwise the GHC runtime will terminate
+-- with a division-by-zero fault.
+integerDivMod :: Integer -> Integer -> (Integer, Integer)
+integerDivMod !n !d = case integerDivMod# n d of
+ (# q,r #) -> (q,r)
+
+
+integerDiv :: Integer -> Integer -> Integer
+{-# NOINLINE integerDiv #-}
+integerDiv !n !d
+ -- same-sign ops can be handled by more efficient 'integerQuot'
+ | isTrue# (integerIsNegative# n ==# integerIsNegative# d) = integerQuot n d
+ | True = case integerDivMod# n d of (# q, _ #) -> q
+
+
+integerMod :: Integer -> Integer -> Integer
+{-# NOINLINE integerMod #-}
+integerMod !n !d
+ -- same-sign ops can be handled by more efficient 'integerRem'
+ | isTrue# (integerIsNegative# n ==# integerIsNegative# d) = integerRem n d
+ | True = case integerDivMod# n d of (# _, r #) -> r
+
+-- | Compute greatest common divisor.
+integerGcd :: Integer -> Integer -> Integer
+{-# NOINLINE integerGcd #-}
+integerGcd (IS 0#) !b = integerAbs b
+integerGcd a (IS 0#) = integerAbs a
+integerGcd (IS 1#) _ = IS 1#
+integerGcd (IS -1#) _ = IS 1#
+integerGcd _ (IS 1#) = IS 1#
+integerGcd _ (IS -1#) = IS 1#
+integerGcd (IS a) (IS b) = integerFromWord# (gcdWord#
+ (int2Word# (absI# a))
+ (int2Word# (absI# b)))
+integerGcd a@(IS _) b = integerGcd b a
+integerGcd (IN a) b = integerGcd (IP a) b
+integerGcd (IP a) (IP b) = integerFromBigNat (bigNatGcd a b)
+integerGcd (IP a) (IN b) = integerFromBigNat (bigNatGcd a b)
+integerGcd (IP a) (IS b) = integerFromWord# (bigNatGcdWord# a (int2Word# (absI# b)))
+
+-- | Compute least common multiple.
+integerLcm :: Integer -> Integer -> Integer
+{-# NOINLINE integerLcm #-}
+integerLcm (IS 0#) !_ = IS 0#
+integerLcm (IS 1#) b = integerAbs b
+integerLcm (IS -1#) b = integerAbs b
+integerLcm _ (IS 0#) = IS 0#
+integerLcm a (IS 1#) = integerAbs a
+integerLcm a (IS -1#) = integerAbs a
+integerLcm a b = (aa `integerQuot` (aa `integerGcd` ab)) `integerMul` ab
+ where -- TODO: use extended GCD to get a's factor directly
+ aa = integerAbs a
+ ab = integerAbs b
+
+-- | Square a Integer
+integerSqr :: Integer -> Integer
+integerSqr !a = integerMul a a
+
+
+-- | Base 2 logarithm (floor)
+--
+-- For numbers <= 0, return 0
+integerLog2# :: Integer -> Word#
+integerLog2# (IS i)
+ | isTrue# (i <=# 0#) = 0##
+ | True = wordLog2# (int2Word# i)
+integerLog2# (IN _) = 0##
+integerLog2# (IP b) = bigNatLog2# b
+
+-- | Base 2 logarithm (floor)
+--
+-- For numbers <= 0, return 0
+integerLog2 :: Integer -> Word
+integerLog2 !i = W# (integerLog2# i)
+
+-- | Logarithm (floor) for an arbitrary base
+--
+-- For numbers <= 0, return 0
+integerLogBaseWord# :: Word# -> Integer -> Word#
+integerLogBaseWord# base !i
+ | integerIsNegative i = 0##
+ | True = naturalLogBaseWord# base (integerToNatural i)
+
+-- | Logarithm (floor) for an arbitrary base
+--
+-- For numbers <= 0, return 0
+integerLogBaseWord :: Word -> Integer -> Word
+integerLogBaseWord (W# base) !i = W# (integerLogBaseWord# base i)
+
+-- | Logarithm (floor) for an arbitrary base
+--
+-- For numbers <= 0, return 0
+integerLogBase# :: Integer -> Integer -> Word#
+integerLogBase# !base !i
+ | integerIsNegative i = 0##
+ | True = naturalLogBase# (integerToNatural base)
+ (integerToNatural i)
+
+-- | Logarithm (floor) for an arbitrary base
+--
+-- For numbers <= 0, return 0
+integerLogBase :: Integer -> Integer -> Word
+integerLogBase !base !i = W# (integerLogBase# base i)
+
+-- | Indicate if the value is a power of two and which one
+integerIsPowerOf2# :: Integer -> (# () | Word# #)
+integerIsPowerOf2# (IS i)
+ | isTrue# (i <=# 0#) = (# () | #)
+ | True = wordIsPowerOf2# (int2Word# i)
+integerIsPowerOf2# (IN _) = (# () | #)
+integerIsPowerOf2# (IP w) = bigNatIsPowerOf2# w
+
+#if WORD_SIZE_IN_BITS == 32
+
+-- | Convert an Int64# into an Integer on 32-bit architectures
+integerFromInt64# :: Int64# -> Integer
+{-# NOINLINE integerFromInt64# #-}
+integerFromInt64# !i
+ | isTrue# ((i `leInt64#` intToInt64# 0x7FFFFFFF#)
+ &&# (i `geInt64#` intToInt64# -0x80000000#))
+ = IS (int64ToInt# i)
+
+ | isTrue# (i `geInt64#` intToInt64# 0#)
+ = IP (bigNatFromWord64# (int64ToWord64# i))
+
+ | True
+ = IN (bigNatFromWord64# (int64ToWord64# (negateInt64# i)))
+
+-- | Convert a Word64# into an Integer on 32-bit architectures
+integerFromWord64# :: Word64# -> Integer
+{-# NOINLINE integerFromWord64# #-}
+integerFromWord64# !w
+ | isTrue# (w `leWord64#` wordToWord64# 0x7FFFFFFF##)
+ = IS (int64ToInt# (word64ToInt64# w))
+ | True
+ = IP (bigNatFromWord64# w)
+
+-- | Convert an Integer into an Int64# on 32-bit architectures
+integerToInt64# :: Integer -> Int64#
+{-# NOINLINE integerToInt64# #-}
+integerToInt64# (IS i) = intToInt64# i
+integerToInt64# (IP b) = word64ToInt64# (bigNatToWord64# b)
+integerToInt64# (IN b) = negateInt64# (word64ToInt64# (bigNatToWord64# b))
+
+-- | Convert an Integer into a Word64# on 32-bit architectures
+integerToWord64# :: Integer -> Word64#
+{-# NOINLINE integerToWord64# #-}
+integerToWord64# (IS i) = int64ToWord64# (intToInt64# i)
+integerToWord64# (IP b) = bigNatToWord64# b
+integerToWord64# (IN b) = int64ToWord64# (negateInt64# (word64ToInt64# (bigNatToWord64# b)))
+
+#else
+
+-- | Convert an Int64# into an Integer on 64-bit architectures
+integerFromInt64# :: Int# -> Integer
+integerFromInt64# !x = IS x
+
+#endif
+
+----------------------------------------------------------------------------
+-- Conversions to/from floating point
+----------------------------------------------------------------------------
+
+-- | Decode a Double# into (# Integer mantissa, Int# exponent #)
+integerDecodeDouble# :: Double# -> (# Integer, Int# #)
+{-# NOINLINE integerDecodeDouble# #-}
+integerDecodeDouble# !x = case decodeDouble_Int64# x of
+ (# m, e #) -> (# integerFromInt64# m, e #)
+
+-- | Decode a Double# into (# Integer mantissa, Int# exponent #)
+integerDecodeDouble :: Double -> (Integer, Int)
+integerDecodeDouble (D# x) = case integerDecodeDouble# x of
+ (# m, e #) -> (m, I# e)
+
+-- | Encode (# Integer mantissa, Int# exponent #) into a Double#
+integerEncodeDouble# :: Integer -> Int# -> Double#
+{-# NOINLINE integerEncodeDouble# #-}
+integerEncodeDouble# (IS i) 0# = int2Double# i
+integerEncodeDouble# (IS i) e = intEncodeDouble# i e
+integerEncodeDouble# (IP b) e = bigNatEncodeDouble# b e
+integerEncodeDouble# (IN b) e = negateDouble# (bigNatEncodeDouble# b e)
+
+-- | Encode (Integer mantissa, Int exponent) into a Double
+integerEncodeDouble :: Integer -> Int -> Double
+integerEncodeDouble !m (I# e) = D# (integerEncodeDouble# m e)
+
+-- | Encode an Integer (mantissa) into a Double#
+integerToDouble# :: Integer -> Double#
+{-# NOINLINE integerToDouble# #-}
+integerToDouble# !i = integerEncodeDouble# i 0#
+
+-- | Encode an Integer (mantissa) into a Float#
+integerToFloat# :: Integer -> Float#
+{-# NOINLINE integerToFloat# #-}
+integerToFloat# !i = integerEncodeFloat# i 0#
+
+-- | Encode (# Integer mantissa, Int# exponent #) into a Float#
+--
+-- TODO: Not sure if it's worth to write 'Float' optimized versions here
+integerEncodeFloat# :: Integer -> Int# -> Float#
+{-# NOINLINE integerEncodeFloat# #-}
+integerEncodeFloat# !m 0# = double2Float# (integerToDouble# m)
+integerEncodeFloat# !m e = double2Float# (integerEncodeDouble# m e)
+
+-- | Compute the number of digits of the Integer (without the sign) in the given base.
+--
+-- `base` must be > 1
+integerSizeInBase# :: Word# -> Integer -> Word#
+integerSizeInBase# base (IS i) = wordSizeInBase# base (int2Word# (absI# i))
+integerSizeInBase# base (IP n) = bigNatSizeInBase# base n
+integerSizeInBase# base (IN n) = bigNatSizeInBase# base n
+
+-- | Write an 'Integer' (without sign) to @/addr/@ in base-256 representation
+-- and return the number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: write most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+integerToAddr# :: Integer -> Addr# -> Bool# -> State# s -> (# State# s, Word# #)
+integerToAddr# (IS i) = wordToAddr# (int2Word# (absI# i))
+integerToAddr# (IP n) = bigNatToAddr# n
+integerToAddr# (IN n) = bigNatToAddr# n
+
+-- | Write an 'Integer' (without sign) to @/addr/@ in base-256 representation
+-- and return the number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: write most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+integerToAddr :: Integer -> Addr# -> Bool# -> IO Word
+integerToAddr a addr e = IO \s -> case integerToAddr# a addr e s of
+ (# s', w #) -> (# s', W# w #)
+
+-- | Read an 'Integer' (without sign) in base-256 representation from an Addr#.
+--
+-- The size is given in bytes.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Null higher limbs are automatically trimed.
+integerFromAddr# :: Word# -> Addr# -> Bool# -> State# s -> (# State# s, Integer #)
+integerFromAddr# sz addr e s =
+ case bigNatFromAddr# sz addr e s of
+ (# s', n #) -> (# s', integerFromBigNat n #)
+
+-- | Read an 'Integer' (without sign) in base-256 representation from an Addr#.
+--
+-- The size is given in bytes.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Null higher limbs are automatically trimed.
+integerFromAddr :: Word# -> Addr# -> Bool# -> IO Integer
+integerFromAddr sz addr e = IO (integerFromAddr# sz addr e)
+
+
+
+-- | Write an 'Integer' (without sign) in base-256 representation and return the
+-- number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+integerToMutableByteArray# :: Integer -> MutableByteArray# s -> Word# -> Bool# -> State# s -> (# State# s, Word# #)
+integerToMutableByteArray# (IS i) = wordToMutableByteArray# (int2Word# (absI# i))
+integerToMutableByteArray# (IP a) = bigNatToMutableByteArray# a
+integerToMutableByteArray# (IN a) = bigNatToMutableByteArray# a
+
+-- | Write an 'Integer' (without sign) in base-256 representation and return the
+-- number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+integerToMutableByteArray :: Integer -> MutableByteArray# RealWorld -> Word# -> Bool# -> IO Word
+integerToMutableByteArray i mba w e = IO \s -> case integerToMutableByteArray# i mba w e s of
+ (# s', r #) -> (# s', W# r #)
+
+-- | Read an 'Integer' (without sign) in base-256 representation from a ByteArray#.
+--
+-- The size is given in bytes.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Null higher limbs are automatically trimed.
+integerFromByteArray# :: Word# -> ByteArray# -> Word# -> Bool# -> State# s -> (# State# s, Integer #)
+integerFromByteArray# sz ba off e s = case bigNatFromByteArray# sz ba off e s of
+ (# s', a #) -> (# s', integerFromBigNat a #)
+
+-- | Read an 'Integer' (without sign) in base-256 representation from a ByteArray#.
+--
+-- The size is given in bytes.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Null higher limbs are automatically trimed.
+integerFromByteArray :: Word# -> ByteArray# -> Word# -> Bool# -> Integer
+integerFromByteArray sz ba off e = case runRW# (integerFromByteArray# sz ba off e) of
+ (# _, i #) -> i
diff --git a/libraries/ghc-bignum/src/GHC/Num/Natural.hs b/libraries/ghc-bignum/src/GHC/Num/Natural.hs
new file mode 100644
index 0000000000..1adb02181d
--- /dev/null
+++ b/libraries/ghc-bignum/src/GHC/Num/Natural.hs
@@ -0,0 +1,557 @@
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE BlockArguments #-}
+
+#include "MachDeps.h"
+#include "WordSize.h"
+
+module GHC.Num.Natural where
+
+import GHC.Prim
+import GHC.Types
+import GHC.Classes
+
+import GHC.Num.BigNat
+import GHC.Num.Primitives
+
+default ()
+
+-- | Natural number
+--
+-- Invariant: numbers <= WORD_MAXBOUND use the `NS` constructor
+data Natural
+ = NS !Word#
+ | NB !BigNat
+
+instance Eq Natural where
+ (==) = naturalEq
+ (/=) = naturalNe
+
+instance Ord Natural where
+ compare = naturalCompare
+
+
+-- | Check Natural invariants
+naturalCheck# :: Natural -> Bool#
+naturalCheck# (NS _) = 1#
+naturalCheck# (NB bn) = bigNatCheck# bn &&# bigNatSize# bn ># 1#
+
+-- | Check Natural invariants
+naturalCheck :: Natural -> Bool
+naturalCheck !n = isTrue# (naturalCheck# n)
+
+-- | Zero Natural
+naturalZero :: Natural
+naturalZero = NS 0##
+
+-- | One Natural
+naturalOne :: Natural
+naturalOne = NS 1##
+
+-- | Test Zero Natural
+naturalIsZero :: Natural -> Bool
+naturalIsZero (NS 0##) = True
+naturalIsZero _ = False
+
+-- | Test One Natural
+naturalIsOne :: Natural -> Bool
+naturalIsOne (NS 1##) = True
+naturalIsOne _ = False
+
+-- | Indicate if the value is a power of two and which one
+naturalIsPowerOf2# :: Natural -> (# () | Word# #)
+naturalIsPowerOf2# (NS w) = wordIsPowerOf2# w
+naturalIsPowerOf2# (NB w) = bigNatIsPowerOf2# w
+
+-- | Create a Natural from a BigNat (respect the invariants)
+naturalFromBigNat :: BigNat -> Natural
+naturalFromBigNat x = case bigNatSize# x of
+ 0# -> naturalZero
+ 1# -> NS (bigNatIndex# x 0#)
+ _ -> NB x
+
+-- | Convert a Natural into a BigNat
+naturalToBigNat :: Natural -> BigNat
+naturalToBigNat (NS w) = bigNatFromWord# w
+naturalToBigNat (NB bn) = bn
+
+-- | Create a Natural from a Word#
+naturalFromWord# :: Word# -> Natural
+{-# NOINLINE naturalFromWord# #-}
+naturalFromWord# x = NS x
+
+-- | Convert two Word# (most-significant first) into a Natural
+naturalFromWord2# :: Word# -> Word# -> Natural
+naturalFromWord2# 0## 0## = naturalZero
+naturalFromWord2# 0## n = NS n
+naturalFromWord2# w1 w2 = NB (bigNatFromWord2# w2 w1)
+
+-- | Create a Natural from a Word
+naturalFromWord :: Word -> Natural
+naturalFromWord (W# x) = NS x
+
+-- | Create a Natural from a list of Word
+naturalFromWordList :: [Word] -> Natural
+naturalFromWordList xs = naturalFromBigNat (bigNatFromWordList xs)
+
+-- | Convert the lower bits of a Natural into a Word#
+naturalToWord# :: Natural -> Word#
+{-# NOINLINE naturalToWord# #-}
+naturalToWord# (NS x) = x
+naturalToWord# (NB b) = bigNatIndex# b 0#
+
+-- | Convert the lower bits of a Natural into a Word
+naturalToWord :: Natural -> Word
+naturalToWord !n = W# (naturalToWord# n)
+
+
+-- | Try downcasting 'Natural' to 'Word' value.
+-- Returns '()' if value doesn't fit in 'Word'.
+naturalToWordMaybe# :: Natural -> (# Word# | () #)
+naturalToWordMaybe# (NS w) = (# w | #)
+naturalToWordMaybe# _ = (# | () #)
+
+-- | Create a Natural from an Int# (unsafe: silently converts negative values
+-- into positive ones)
+naturalFromIntUnsafe# :: Int# -> Natural
+naturalFromIntUnsafe# !i = NS (int2Word# i)
+
+-- | Create a Natural from an Int (unsafe: silently converts negative values
+-- into positive ones)
+naturalFromIntUnsafe :: Int -> Natural
+naturalFromIntUnsafe (I# i) = naturalFromIntUnsafe# i
+
+-- | Create a Natural from an Int#
+--
+-- Throws 'Control.Exception.Underflow' when passed a negative 'Int'.
+naturalFromIntThrow# :: Int# -> Natural
+naturalFromIntThrow# i
+ | isTrue# (i <# 0#) = case underflow of _ -> NS 0##
+ | True = naturalFromIntUnsafe# i
+
+-- | Create a Natural from an Int
+--
+-- Throws 'Control.Exception.Underflow' when passed a negative 'Int'.
+naturalFromIntThrow :: Int -> Natural
+naturalFromIntThrow (I# i) = naturalFromIntThrow# i
+
+-- | Create an Int# from a Natural (can overflow the int and give a negative
+-- number)
+naturalToInt# :: Natural -> Int#
+naturalToInt# !n = word2Int# (naturalToWord# n)
+
+-- | Create an Int# from a Natural (can overflow the int and give a negative
+-- number)
+naturalToInt :: Natural -> Int
+naturalToInt !n = I# (naturalToInt# n)
+
+-- | Create a Natural from an Int#
+--
+-- Underflow exception if Int# is negative
+naturalFromInt# :: Int# -> Natural
+naturalFromInt# !i
+ | isTrue# (i >=# 0#) = NS (int2Word# i)
+ | True = case underflow of _ -> NS 0##
+
+-- | Create a Natural from an Int
+--
+-- Underflow exception if Int# is negative
+naturalFromInt :: Int -> Natural
+naturalFromInt (I# i) = naturalFromInt# i
+
+-- | Encode (# Natural mantissa, Int# exponent #) into a Double#
+naturalEncodeDouble# :: Natural -> Int# -> Double#
+naturalEncodeDouble# (NS w) 0# = word2Double# w
+naturalEncodeDouble# (NS w) e = wordEncodeDouble# w e
+naturalEncodeDouble# (NB b) e = bigNatEncodeDouble# b e
+
+-- | Encode a Natural (mantissa) into a Double#
+naturalToDouble# :: Natural -> Double#
+naturalToDouble# !n = naturalEncodeDouble# n 0#
+
+-- | Encode an Natural (mantissa) into a Float#
+naturalToFloat# :: Natural -> Float#
+naturalToFloat# !i = naturalEncodeFloat# i 0#
+
+-- | Encode (# Natural mantissa, Int# exponent #) into a Float#
+--
+-- TODO: Not sure if it's worth to write 'Float' optimized versions here
+naturalEncodeFloat# :: Natural -> Int# -> Float#
+naturalEncodeFloat# !m 0# = double2Float# (naturalToDouble# m)
+naturalEncodeFloat# !m e = double2Float# (naturalEncodeDouble# m e)
+
+-- | Equality test for Natural
+naturalEq# :: Natural -> Natural -> Bool#
+naturalEq# (NS x) (NS y) = x `eqWord#` y
+naturalEq# (NB x) (NB y) = bigNatEq# x y
+naturalEq# _ _ = 0#
+
+-- | Equality test for Natural
+naturalEq :: Natural -> Natural -> Bool
+naturalEq !x !y = isTrue# (naturalEq# x y)
+
+-- | Inequality test for Natural
+naturalNe# :: Natural -> Natural -> Bool#
+naturalNe# (NS x) (NS y) = x `neWord#` y
+naturalNe# (NB x) (NB y) = bigNatNe# x y
+naturalNe# _ _ = 1#
+
+-- | Inequality test for Natural
+naturalNe :: Natural -> Natural -> Bool
+naturalNe !x !y = isTrue# (naturalNe# x y)
+
+-- | Compare two Natural
+naturalCompare :: Natural -> Natural -> Ordering
+naturalCompare (NS x) (NS y) = compare (W# x) (W# y)
+naturalCompare (NB x) (NB y) = bigNatCompare x y
+naturalCompare (NS _) (NB _) = LT
+naturalCompare (NB _) (NS _) = GT
+
+-- | PopCount for Natural
+naturalPopCount# :: Natural -> Word#
+naturalPopCount# (NS x) = popCnt# x
+naturalPopCount# (NB x) = bigNatPopCount# x
+
+-- | PopCount for Natural
+naturalPopCount :: Natural -> Word
+naturalPopCount (NS x) = W# (popCnt# x)
+naturalPopCount (NB x) = bigNatPopCount x
+
+-- | Right shift for Natural
+naturalShiftR# :: Natural -> Word# -> Natural
+naturalShiftR# (NS x) n = NS (x `shiftRW#` n)
+naturalShiftR# (NB x) n = naturalFromBigNat (x `bigNatShiftR#` n)
+
+-- | Right shift for Natural
+naturalShiftR :: Natural -> Word -> Natural
+naturalShiftR x (W# n) = naturalShiftR# x n
+
+-- | Left shift
+naturalShiftL# :: Natural -> Word# -> Natural
+naturalShiftL# (NS x) n
+ | isTrue# (clz# x `geWord#` n) = NS (x `uncheckedShiftL#` word2Int# n)
+ | True = NB (bigNatFromWord# x `bigNatShiftL#` n)
+naturalShiftL# (NB x) n = NB (x `bigNatShiftL#` n)
+
+-- | Left shift
+naturalShiftL :: Natural -> Word -> Natural
+naturalShiftL !x (W# n) = naturalShiftL# x n
+
+-- | Add two naturals
+naturalAdd :: Natural -> Natural -> Natural
+{-# NOINLINE naturalAdd #-}
+naturalAdd (NS x) (NB y) = NB (bigNatAddWord# y x)
+naturalAdd (NB x) (NS y) = NB (bigNatAddWord# x y)
+naturalAdd (NB x) (NB y) = NB (bigNatAdd x y)
+naturalAdd (NS x) (NS y) =
+ case addWordC# x y of
+ (# l,0# #) -> NS l
+ (# l,c #) -> NB (bigNatFromWord2# (int2Word# c) l)
+
+-- | Sub two naturals
+naturalSub :: Natural -> Natural -> (# () | Natural #)
+{-# NOINLINE naturalSub #-}
+naturalSub (NS _) (NB _) = (# () | #)
+naturalSub (NB x) (NS y) = (# | naturalFromBigNat (bigNatSubWordUnsafe# x y) #)
+naturalSub (NS x) (NS y) =
+ case subWordC# x y of
+ (# l,0# #) -> (# | NS l #)
+ (# _,_ #) -> (# () | #)
+naturalSub (NB x) (NB y) =
+ case bigNatSub x y of
+ (# () | #) -> (# () | #)
+ (# | z #) -> (# | naturalFromBigNat z #)
+
+-- | Sub two naturals
+--
+-- Throw an Underflow exception if x < y
+naturalSubThrow :: Natural -> Natural -> Natural
+naturalSubThrow (NS _) (NB _) = case underflow of _ -> NS 0##
+naturalSubThrow (NB x) (NS y) = naturalFromBigNat (bigNatSubWordUnsafe# x y)
+naturalSubThrow (NS x) (NS y) =
+ case subWordC# x y of
+ (# l,0# #) -> NS l
+ (# _,_ #) -> case underflow of _ -> NS 0##
+naturalSubThrow (NB x) (NB y) =
+ case bigNatSub x y of
+ (# () | #) -> case underflow of _ -> NS 0##
+ (# | z #) -> naturalFromBigNat z
+
+-- | Sub two naturals
+--
+-- Unsafe: don't check that x >= y
+-- Undefined results if it happens
+naturalSubUnsafe :: Natural -> Natural -> Natural
+{-# NOINLINE naturalSubUnsafe #-}
+naturalSubUnsafe (NS x) (NS y) = NS (minusWord# x y)
+naturalSubUnsafe (NS _) (NB _) = naturalZero
+naturalSubUnsafe (NB x) (NS y) = naturalFromBigNat (bigNatSubWordUnsafe# x y)
+naturalSubUnsafe (NB x) (NB y) =
+ case bigNatSub x y of
+ (# () | #) -> naturalZero
+ (# | z #) -> naturalFromBigNat z
+
+-- | Multiplication
+naturalMul :: Natural -> Natural -> Natural
+{-# NOINLINE naturalMul #-}
+naturalMul a b = case a of
+ NS 0## -> NS 0##
+ NS 1## -> b
+ NS x -> case b of
+ NS 0## -> NS 0##
+ NS 1## -> a
+ NS y -> case timesWord2# x y of
+ (# h,l #) -> naturalFromWord2# h l
+ NB y -> NB (bigNatMulWord# y x)
+ NB x -> case b of
+ NS 0## -> NS 0##
+ NS 1## -> a
+ NS y -> NB (bigNatMulWord# x y)
+ NB y -> NB (bigNatMul x y)
+
+-- | Square a Natural
+naturalSqr :: Natural -> Natural
+naturalSqr !a = naturalMul a a
+
+-- | Signum for Natural
+naturalSignum :: Natural -> Natural
+naturalSignum (NS 0##) = NS 0##
+naturalSignum _ = NS 1##
+
+-- | Negate for Natural
+naturalNegate :: Natural -> Natural
+{-# NOINLINE naturalNegate #-}
+naturalNegate (NS 0##) = NS 0##
+naturalNegate _ = case underflow of _ -> NS 0##
+
+-- | Return division quotient and remainder
+--
+-- Division by zero is handled by BigNat
+naturalQuotRem# :: Natural -> Natural -> (# Natural, Natural #)
+{-# NOINLINE naturalQuotRem# #-}
+naturalQuotRem# (NS n) (NS d) = case quotRemWord# n d of
+ (# q, r #) -> (# NS q, NS r #)
+naturalQuotRem# (NB n) (NS d) = case bigNatQuotRemWord# n d of
+ (# q, r #) -> (# naturalFromBigNat q, NS r #)
+naturalQuotRem# (NS n) (NB d) = case bigNatQuotRem# (bigNatFromWord# n) d of
+ (# q, r #) -> (# naturalFromBigNat q, naturalFromBigNat r #)
+naturalQuotRem# (NB n) (NB d) = case bigNatQuotRem# n d of
+ (# q, r #) -> (# naturalFromBigNat q, naturalFromBigNat r #)
+
+-- | Return division quotient and remainder
+naturalQuotRem :: Natural -> Natural -> (Natural, Natural)
+naturalQuotRem !n !d = case naturalQuotRem# n d of
+ (# q, r #) -> (q,r)
+
+-- | Return division quotient
+naturalQuot :: Natural -> Natural -> Natural
+{-# NOINLINE naturalQuot #-}
+naturalQuot (NS n) (NS d) = case quotWord# n d of
+ q -> NS q
+naturalQuot (NB n) (NS d) = case bigNatQuotWord# n d of
+ q -> naturalFromBigNat q
+naturalQuot (NS n) (NB d) = case bigNatQuot (bigNatFromWord# n) d of
+ q -> naturalFromBigNat q
+naturalQuot (NB n) (NB d) = case bigNatQuot n d of
+ q -> naturalFromBigNat q
+
+-- | Return division remainder
+naturalRem :: Natural -> Natural -> Natural
+{-# NOINLINE naturalRem #-}
+naturalRem (NS n) (NS d) = case remWord# n d of
+ r -> NS r
+naturalRem (NB n) (NS d) = case bigNatRemWord# n d of
+ r -> NS r
+naturalRem (NS n) (NB d) = case bigNatRem (bigNatFromWord# n) d of
+ r -> naturalFromBigNat r
+naturalRem (NB n) (NB d) = case bigNatRem n d of
+ r -> naturalFromBigNat r
+
+naturalAnd :: Natural -> Natural -> Natural
+naturalAnd (NS n) (NS m) = NS (n `and#` m)
+naturalAnd (NS n) (NB m) = NS (n `and#` bigNatToWord# m)
+naturalAnd (NB n) (NS m) = NS (bigNatToWord# n `and#` m)
+naturalAnd (NB n) (NB m) = naturalFromBigNat (bigNatAnd n m)
+
+naturalAndNot :: Natural -> Natural -> Natural
+naturalAndNot (NS n) (NS m) = NS (n `and#` not# m)
+naturalAndNot (NS n) (NB m) = NS (n `and#` not# (bigNatToWord# m))
+naturalAndNot (NB n) (NS m) = NS (bigNatToWord# n `and#` not# m)
+naturalAndNot (NB n) (NB m) = naturalFromBigNat (bigNatAndNot n m)
+
+naturalOr :: Natural -> Natural -> Natural
+naturalOr (NS n) (NS m) = NS (n `or#` m)
+naturalOr (NS n) (NB m) = NB (bigNatOrWord# m n)
+naturalOr (NB n) (NS m) = NB (bigNatOrWord# n m)
+naturalOr (NB n) (NB m) = NB (bigNatOr n m)
+
+naturalXor :: Natural -> Natural -> Natural
+naturalXor (NS n) (NS m) = NS (n `xor#` m)
+naturalXor (NS n) (NB m) = NB (bigNatXorWord# m n)
+naturalXor (NB n) (NS m) = NB (bigNatXorWord# n m)
+naturalXor (NB n) (NB m) = naturalFromBigNat (bigNatXor n m)
+
+naturalTestBit# :: Natural -> Word# -> Bool#
+naturalTestBit# (NS w) i = (i `ltWord#` WORD_SIZE_IN_BITS##) &&#
+ ((w `and#` (1## `uncheckedShiftL#` word2Int# i)) `neWord#` 0##)
+naturalTestBit# (NB bn) i = bigNatTestBit# bn i
+
+naturalTestBit :: Natural -> Word -> Bool
+naturalTestBit !n (W# i) = isTrue# (naturalTestBit# n i)
+
+naturalBit# :: Word# -> Natural
+naturalBit# i
+ | isTrue# (i `ltWord#` WORD_SIZE_IN_BITS##) = NS (1## `uncheckedShiftL#` word2Int# i)
+ | True = NB (bigNatBit# i)
+
+naturalBit :: Word -> Natural
+naturalBit (W# i) = naturalBit# i
+
+-- | Compute greatest common divisor.
+naturalGcd :: Natural -> Natural -> Natural
+naturalGcd (NS 0##) !y = y
+naturalGcd x (NS 0##) = x
+naturalGcd (NS 1##) _ = NS 1##
+naturalGcd _ (NS 1##) = NS 1##
+naturalGcd (NB x) (NB y) = naturalFromBigNat (bigNatGcd x y)
+naturalGcd (NB x) (NS y) = NS (bigNatGcdWord# x y)
+naturalGcd (NS x) (NB y) = NS (bigNatGcdWord# y x)
+naturalGcd (NS x) (NS y) = NS (gcdWord# x y)
+
+-- | Compute least common multiple.
+naturalLcm :: Natural -> Natural -> Natural
+naturalLcm (NS 0##) !_ = NS 0##
+naturalLcm _ (NS 0##) = NS 0##
+naturalLcm (NS 1##) y = y
+naturalLcm x (NS 1##) = x
+naturalLcm (NS a ) (NS b ) = naturalFromBigNat (bigNatLcmWordWord# a b)
+naturalLcm (NB a ) (NS b ) = naturalFromBigNat (bigNatLcmWord# a b)
+naturalLcm (NS a ) (NB b ) = naturalFromBigNat (bigNatLcmWord# b a)
+naturalLcm (NB a ) (NB b ) = naturalFromBigNat (bigNatLcm a b)
+
+-- | Base 2 logarithm
+naturalLog2# :: Natural -> Word#
+naturalLog2# (NS w) = wordLog2# w
+naturalLog2# (NB b) = bigNatLog2# b
+
+-- | Base 2 logarithm
+naturalLog2 :: Natural -> Word
+naturalLog2 !n = W# (naturalLog2# n)
+
+-- | Logarithm for an arbitrary base
+naturalLogBaseWord# :: Word# -> Natural -> Word#
+naturalLogBaseWord# base (NS a) = wordLogBase# base a
+naturalLogBaseWord# base (NB a) = bigNatLogBaseWord# base a
+
+-- | Logarithm for an arbitrary base
+naturalLogBaseWord :: Word -> Natural -> Word
+naturalLogBaseWord (W# base) !a = W# (naturalLogBaseWord# base a)
+
+-- | Logarithm for an arbitrary base
+naturalLogBase# :: Natural -> Natural -> Word#
+naturalLogBase# (NS base) !a = naturalLogBaseWord# base a
+naturalLogBase# (NB _ ) (NS _) = 0##
+naturalLogBase# (NB base) (NB a) = bigNatLogBase# base a
+
+-- | Logarithm for an arbitrary base
+naturalLogBase :: Natural -> Natural -> Word
+naturalLogBase !base !a = W# (naturalLogBase# base a)
+
+-- | \"@'naturalPowMod' /b/ /e/ /m/@\" computes base @/b/@ raised to
+-- exponent @/e/@ modulo @/m/@.
+naturalPowMod :: Natural -> Natural -> Natural -> Natural
+naturalPowMod !_ !_ (NS 0##) = case divByZero of _ -> naturalZero
+naturalPowMod _ _ (NS 1##) = NS 0##
+naturalPowMod _ (NS 0##) _ = NS 1##
+naturalPowMod (NS 0##) _ _ = NS 0##
+naturalPowMod (NS 1##) _ _ = NS 1##
+naturalPowMod (NS b) (NS e) (NS m) = NS (powModWord# b e m)
+naturalPowMod b e (NS m) = NS (bigNatPowModWord#
+ (naturalToBigNat b)
+ (naturalToBigNat e)
+ m)
+naturalPowMod b e (NB m) = naturalFromBigNat
+ (bigNatPowMod (naturalToBigNat b)
+ (naturalToBigNat e)
+ m)
+
+-- | Compute the number of digits of the Natural in the given base.
+--
+-- `base` must be > 1
+naturalSizeInBase# :: Word# -> Natural -> Word#
+naturalSizeInBase# base (NS w) = wordSizeInBase# base w
+naturalSizeInBase# base (NB n) = bigNatSizeInBase# base n
+
+-- | Write a 'Natural' to @/addr/@ in base-256 representation and return the
+-- number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: write most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+naturalToAddr# :: Natural -> Addr# -> Bool# -> State# s -> (# State# s, Word# #)
+naturalToAddr# (NS i) = wordToAddr# i
+naturalToAddr# (NB n) = bigNatToAddr# n
+
+-- | Write a 'Natural' to @/addr/@ in base-256 representation and return the
+-- number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: write most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+naturalToAddr :: Natural -> Addr# -> Bool# -> IO Word
+naturalToAddr a addr e = IO \s -> case naturalToAddr# a addr e s of
+ (# s', w #) -> (# s', W# w #)
+
+
+-- | Read a Natural in base-256 representation from an Addr#.
+--
+-- The size is given in bytes.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Null higher limbs are automatically trimed.
+naturalFromAddr# :: Word# -> Addr# -> Bool# -> State# s -> (# State# s, Natural #)
+naturalFromAddr# sz addr e s =
+ case bigNatFromAddr# sz addr e s of
+ (# s', n #) -> (# s', naturalFromBigNat n #)
+
+-- | Read a Natural in base-256 representation from an Addr#.
+--
+-- The size is given in bytes.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Null higher limbs are automatically trimed.
+naturalFromAddr :: Word# -> Addr# -> Bool# -> IO Natural
+naturalFromAddr sz addr e = IO (naturalFromAddr# sz addr e)
+
+
+-- | Write a Natural in base-256 representation and return the
+-- number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+naturalToMutableByteArray# :: Natural -> MutableByteArray# s -> Word# -> Bool# -> State# s -> (# State# s, Word# #)
+naturalToMutableByteArray# (NS w) = wordToMutableByteArray# w
+naturalToMutableByteArray# (NB a) = bigNatToMutableByteArray# a
+
+-- | Read a Natural in base-256 representation from a ByteArray#.
+--
+-- The size is given in bytes.
+--
+-- The endianness is selected with the Bool# parameter: most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- Null higher limbs are automatically trimed.
+naturalFromByteArray# :: Word# -> ByteArray# -> Word# -> Bool# -> State# s -> (# State# s, Natural #)
+naturalFromByteArray# sz ba off e s = case bigNatFromByteArray# sz ba off e s of
+ (# s', a #) -> (# s', naturalFromBigNat a #)
diff --git a/libraries/ghc-bignum/src/GHC/Num/Natural.hs-boot b/libraries/ghc-bignum/src/GHC/Num/Natural.hs-boot
new file mode 100644
index 0000000000..28cf5d1771
--- /dev/null
+++ b/libraries/ghc-bignum/src/GHC/Num/Natural.hs-boot
@@ -0,0 +1,23 @@
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE MagicHash #-}
+
+module GHC.Num.Natural where
+
+import {-# SOURCE #-} GHC.Num.BigNat
+import GHC.Num.Primitives
+import GHC.Prim
+import GHC.Types
+
+data Natural
+ = NS !Word#
+ | NB !BigNat
+
+naturalToWord# :: Natural -> Word#
+naturalFromWord# :: Word# -> Natural
+naturalToBigNat :: Natural -> BigNat
+naturalFromBigNat :: BigNat -> Natural
+naturalMul :: Natural -> Natural -> Natural
+naturalRem :: Natural -> Natural -> Natural
+naturalIsZero :: Natural -> Bool
+naturalShiftR# :: Natural -> Word# -> Natural
+naturalTestBit# :: Natural -> Word# -> Bool#
diff --git a/libraries/ghc-bignum/src/GHC/Num/Primitives.hs b/libraries/ghc-bignum/src/GHC/Num/Primitives.hs
new file mode 100644
index 0000000000..2c1a0b6955
--- /dev/null
+++ b/libraries/ghc-bignum/src/GHC/Num/Primitives.hs
@@ -0,0 +1,623 @@
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE UnliftedFFITypes #-}
+{-# LANGUAGE NegativeLiterals #-}
+{-# LANGUAGE ExplicitForAll #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE BinaryLiterals #-}
+{-# OPTIONS_GHC -fexpose-all-unfoldings #-}
+
+module GHC.Num.Primitives
+ (
+ -- * Bool#
+ Bool#
+ , (&&#)
+ , (||#)
+ , notB#
+ -- * Int#
+ , testBitI#
+ , minI#
+ , maxI#
+ , sgnI#
+ , absI#
+ , cmpI#
+ , intEncodeDouble#
+ , popCntI#
+ -- * Word#
+ , andNot#
+ , cmpW#
+ , bitW#
+ , maxW#
+ , minW#
+ , testBitW#
+ , shiftRW#
+ , plusWord3#
+ , plusWord12#
+ , quotRemWord3#
+ , wordFromAbsInt#
+ , wordLog2#
+ , wordLogBase#
+ , wordSizeInBase#
+ , wordIsPowerOf2#
+ , wordEncodeDouble#
+ , wordReverseBits#
+ , wordReverseBits32#
+ , wordReverseBytes#
+ -- ** Addr import/export
+ , wordFromAddr#
+ , wordFromAddrLE#
+ , wordFromAddrBE#
+ , wordToAddr#
+ , wordToAddrLE#
+ , wordToAddrBE#
+ , wordWriteAddrLE#
+ , wordWriteAddrBE#
+ -- ** ByteArray import/export
+ , wordFromByteArray#
+ , wordFromByteArrayLE#
+ , wordFromByteArrayBE#
+ , wordToMutableByteArray#
+ , wordToMutableByteArrayLE#
+ , wordToMutableByteArrayBE#
+ , wordWriteMutableByteArrayLE#
+ , wordWriteMutableByteArrayBE#
+ -- * Exception
+ , underflow
+ , divByZero
+ , unexpectedValue
+ -- * IO
+ , ioWord#
+ , ioInt#
+ , ioVoid
+ , ioBool
+ )
+where
+
+#include "MachDeps.h"
+#include "WordSize.h"
+
+-- Required for WORDS_BIGENDIAN
+#include <ghcautoconf.h>
+
+#if (__GLASGOW_HASKELL__ < 811)
+import GHC.Magic
+#endif
+
+import GHC.Prim
+import GHC.Types
+import GHC.Tuple () -- See Note [Depend on GHC.Tuple] in GHC.Base
+
+default ()
+
+----------------------------------
+-- Bool#
+----------------------------------
+
+type Bool# = Int#
+
+(&&#) :: Bool# -> Bool# -> Bool#
+(&&#) = andI#
+
+(||#) :: Bool# -> Bool# -> Bool#
+(||#) = orI#
+
+notB# :: Bool# -> Bool#
+notB# x = x `xorI#` 1#
+
+infixr 3 &&#
+infixr 2 ||#
+
+
+----------------------------------
+-- Int#
+----------------------------------
+
+-- | Branchless `abs`
+absI# :: Int# -> Int#
+absI# i# = (i# `xorI#` nsign) -# nsign
+ where
+ -- nsign = negateInt# (i# <# 0#)
+ nsign = uncheckedIShiftRA# i# (WORD_SIZE_IN_BITS# -# 1#)
+
+-- | Branchless `signum`
+sgnI# :: Int# -> Int#
+sgnI# x# = (x# ># 0#) -# (x# <# 0#)
+
+-- | Population count
+popCntI# :: Int# -> Word#
+popCntI# i = popCnt# (int2Word# i)
+
+-- | Branchless comparison
+cmpI# :: Int# -> Int# -> Int#
+cmpI# x# y# = (x# ># y#) -# (x# <# y#)
+
+testBitI# :: Int# -> Word# -> Bool#
+testBitI# x i = ((uncheckedIShiftL# 1# (word2Int# i)) `andI#` x) /=# 0#
+
+minI# :: Int# -> Int# -> Int#
+minI# x y | isTrue# (x <=# y) = x
+ | True = y
+
+maxI# :: Int# -> Int# -> Int#
+maxI# x y | isTrue# (x >=# y) = x
+ | True = y
+
+-- | Encode (# Int# mantissa, Int# exponent #) into a Double#.
+--
+-- (provided by GHC's RTS)
+foreign import ccall unsafe "__int_encodeDouble"
+ intEncodeDouble# :: Int# -> Int# -> Double#
+
+----------------------------------
+-- Word#
+----------------------------------
+
+andNot# :: Word# -> Word# -> Word#
+andNot# x y = x `and#` (not# y)
+
+cmpW# :: Word# -> Word# -> Ordering
+{-# INLINE cmpW# #-}
+cmpW# x# y#
+ | isTrue# (x# `ltWord#` y#) = LT
+ | isTrue# (x# `eqWord#` y#) = EQ
+ | True = GT
+
+-- | Return the absolute value of the Int# in a Word#
+wordFromAbsInt# :: Int# -> Word#
+wordFromAbsInt# i
+ | isTrue# (i >=# 0#) = int2Word# i
+ | True = int2Word# (negateInt# i)
+
+minW# :: Word# -> Word# -> Word#
+minW# x# y# | isTrue# (x# `leWord#` y#) = x#
+ | True = y#
+
+maxW# :: Word# -> Word# -> Word#
+maxW# x# y# | isTrue# (x# `gtWord#` y#) = x#
+ | True = y#
+
+bitW# :: Int# -> Word#
+bitW# k = 1## `uncheckedShiftL#` k
+
+testBitW# :: Word# -> Word# -> Bool#
+testBitW# w k = w `and#` (1## `uncheckedShiftL#` word2Int# k) `neWord#` 0##
+
+-- | Safe right shift for Word#
+shiftRW# :: Word# -> Word# -> Word#
+shiftRW# a b
+ | isTrue# (b `geWord#` WORD_SIZE_IN_BITS##) = 0##
+ | True = a `uncheckedShiftRL#` (word2Int# b)
+
+-- | (h,l) <- a + (hb,lb)
+plusWord12# :: Word# -> (# Word#,Word# #) -> (# Word#,Word# #)
+{-# INLINABLE plusWord12# #-}
+plusWord12# a0 (# b1,b0 #) = (# m1, m0 #)
+ where
+ !(# t, m0 #) = plusWord2# a0 b0
+ !m1 = plusWord# t b1
+
+-- | Add 3 values together
+plusWord3# :: Word# -> Word# -> Word# -> (# Word#, Word# #)
+{-# INLINABLE plusWord3# #-}
+plusWord3# a b c = (# r1, r0 #)
+ where
+ !(# t1, t0 #) = plusWord2# a b
+ !(# t2, r0 #) = plusWord2# t0 c
+ !r1 = plusWord# t1 t2
+
+
+-- | 2-by-1 large division
+--
+-- Requires:
+-- b0 /= 0
+-- a1 >= b0 (not required, but if not q1=0)
+quotRemWord3# :: (# Word#,Word# #) -> Word# -> (# (# Word#,Word# #),Word# #)
+quotRemWord3# (# a1,a0 #) b0 = (# (# q1, q0 #), r0 #)
+ where
+ !(# q1, r' #) = quotRemWord# a1 b0
+ !(# q0, r0 #) = quotRemWord2# r' a0 b0
+
+
+
+-- | Encode (# Word# mantissa, Int# exponent #) into a Double#.
+--
+-- (provided by GHC's RTS)
+foreign import ccall unsafe "__word_encodeDouble"
+ wordEncodeDouble# :: Word# -> Int# -> Double#
+
+-- | Compute base-2 log of 'Word#'
+--
+-- This is internally implemented as count-leading-zeros machine instruction.
+wordLog2# :: Word# -> Word#
+wordLog2# w = (WORD_SIZE_IN_BITS## `minusWord#` 1##) `minusWord#` (clz# w)
+
+-- | Logarithm for an arbitrary base
+wordLogBase# :: Word# -> Word# -> Word#
+wordLogBase# base a
+ | isTrue# (base `leWord#` 1##)
+ = case unexpectedValue of _ -> 0##
+
+ | 2## <- base
+ = wordLog2# a
+
+ | True
+ = case go base of (# _, e' #) -> e'
+ where
+ goSqr pw = case timesWord2# pw pw of
+ (# 0##, l #) -> go l
+ (# _ , _ #) -> (# a, 0## #)
+ go pw = if isTrue# (a `ltWord#` pw)
+ then (# a, 0## #)
+ else case goSqr pw of
+ (# q, e #) -> if isTrue# (q `ltWord#` pw)
+ then (# q, 2## `timesWord#` e #)
+ else (# q `quotWord#` pw
+ , 2## `timesWord#` e `plusWord#` 1## #)
+
+wordSizeInBase# :: Word# -> Word# -> Word#
+wordSizeInBase# _ 0## = 0##
+wordSizeInBase# base w = 1## `plusWord#` wordLogBase# base w
+
+-- | Indicate if the value is a power of two and which one
+wordIsPowerOf2# :: Word# -> (# () | Word# #)
+wordIsPowerOf2# w
+ | isTrue# (popCnt# w `neWord#` 1##) = (# () | #)
+ | True = (# | ctz# w #)
+
+-- | Reverse bytes in a Word#
+wordReverseBytes# :: Word# -> Word#
+wordReverseBytes# x0 = r
+ where
+#if WORD_SIZE_IN_BITS == 64
+ x1 = ((x0 `and#` 0x00FF00FF00FF00FF##) `uncheckedShiftL#` 8#) `or#` ((x0 `and#` 0xFF00FF00FF00FF00##) `uncheckedShiftRL#` 8#)
+ x2 = ((x1 `and#` 0x0000FFFF0000FFFF##) `uncheckedShiftL#` 16#) `or#` ((x1 `and#` 0xFFFF0000FFFF0000##) `uncheckedShiftRL#` 16#)
+ r = ((x2 `and#` 0x00000000FFFFFFFF##) `uncheckedShiftL#` 32#) `or#` ((x2 `and#` 0xFFFFFFFF00000000##) `uncheckedShiftRL#` 32#)
+#else
+ x1 = ((x0 `and#` 0x00FF00FF##) `uncheckedShiftL#` 8#) `or#` ((x0 `and#` 0xFF00FF00##) `uncheckedShiftRL#` 8#)
+ r = ((x1 `and#` 0x0000FFFF##) `uncheckedShiftL#` 16#) `or#` ((x1 `and#` 0xFFFF0000##) `uncheckedShiftRL#` 16#)
+#endif
+
+
+-- | Reverse bits in a Word#
+wordReverseBits# :: Word# -> Word#
+wordReverseBits# x0 = r
+ where
+#if WORD_SIZE_IN_BITS == 64
+ x1 = ((x0 `and#` 0x5555555555555555##) `uncheckedShiftL#` 1#) `or#` ((x0 `and#` 0xAAAAAAAAAAAAAAAA##) `uncheckedShiftRL#` 1#)
+ x2 = ((x1 `and#` 0x3333333333333333##) `uncheckedShiftL#` 2#) `or#` ((x1 `and#` 0xCCCCCCCCCCCCCCCC##) `uncheckedShiftRL#` 2#)
+ x3 = ((x2 `and#` 0x0F0F0F0F0F0F0F0F##) `uncheckedShiftL#` 4#) `or#` ((x2 `and#` 0xF0F0F0F0F0F0F0F0##) `uncheckedShiftRL#` 4#)
+ x4 = ((x3 `and#` 0x00FF00FF00FF00FF##) `uncheckedShiftL#` 8#) `or#` ((x3 `and#` 0xFF00FF00FF00FF00##) `uncheckedShiftRL#` 8#)
+ x5 = ((x4 `and#` 0x0000FFFF0000FFFF##) `uncheckedShiftL#` 16#) `or#` ((x4 `and#` 0xFFFF0000FFFF0000##) `uncheckedShiftRL#` 16#)
+ r = ((x5 `and#` 0x00000000FFFFFFFF##) `uncheckedShiftL#` 32#) `or#` ((x5 `and#` 0xFFFFFFFF00000000##) `uncheckedShiftRL#` 32#)
+#else
+ x1 = ((x0 `and#` 0x55555555##) `uncheckedShiftL#` 1#) `or#` ((x0 `and#` 0xAAAAAAAA##) `uncheckedShiftRL#` 1#)
+ x2 = ((x1 `and#` 0x33333333##) `uncheckedShiftL#` 2#) `or#` ((x1 `and#` 0xCCCCCCCC##) `uncheckedShiftRL#` 2#)
+ x3 = ((x2 `and#` 0x0F0F0F0F##) `uncheckedShiftL#` 4#) `or#` ((x2 `and#` 0xF0F0F0F0##) `uncheckedShiftRL#` 4#)
+ x4 = ((x3 `and#` 0x00FF00FF##) `uncheckedShiftL#` 8#) `or#` ((x3 `and#` 0xFF00FF00##) `uncheckedShiftRL#` 8#)
+ r = ((x4 `and#` 0x0000FFFF##) `uncheckedShiftL#` 16#) `or#` ((x4 `and#` 0xFFFF0000##) `uncheckedShiftRL#` 16#)
+#endif
+
+-- | Reverse bits in the Word32 subwords composing a Word#
+wordReverseBits32# :: Word# -> Word#
+#if WORD_SIZE_IN_BITS == 64
+wordReverseBits32# x0 = r
+ where
+ x1 = ((x0 `and#` 0x5555555555555555##) `uncheckedShiftL#` 1#) `or#` ((x0 `and#` 0xAAAAAAAAAAAAAAAA##) `uncheckedShiftRL#` 1#)
+ x2 = ((x1 `and#` 0x3333333333333333##) `uncheckedShiftL#` 2#) `or#` ((x1 `and#` 0xCCCCCCCCCCCCCCCC##) `uncheckedShiftRL#` 2#)
+ x3 = ((x2 `and#` 0x0F0F0F0F0F0F0F0F##) `uncheckedShiftL#` 4#) `or#` ((x2 `and#` 0xF0F0F0F0F0F0F0F0##) `uncheckedShiftRL#` 4#)
+ x4 = ((x3 `and#` 0x00FF00FF00FF00FF##) `uncheckedShiftL#` 8#) `or#` ((x3 `and#` 0xFF00FF00FF00FF00##) `uncheckedShiftRL#` 8#)
+ r = ((x4 `and#` 0x0000FFFF0000FFFF##) `uncheckedShiftL#` 16#) `or#` ((x4 `and#` 0xFFFF0000FFFF0000##) `uncheckedShiftRL#` 16#)
+#else
+wordReverseBits32# x0 = wordReverseBits# x0
+#endif
+
+
+-- | Write a Word to @/addr/@ in base-256 little-endian representation and
+-- return the number of bytes written.
+wordToAddrLE# :: Word# -> Addr# -> State# s -> (# State# s, Word# #)
+wordToAddrLE# x addr = go x 0#
+ where
+ go w c s
+ | 0## <- w
+ = (# s, int2Word# c #)
+
+ | True
+ = case writeWord8OffAddr# addr c (w `and#` 0xFF##) s of
+ s' -> go (w `uncheckedShiftRL#` 8#) (c +# 1#) s'
+
+-- | Write a Word to @/addr/@ in base-256 big-endian representation and
+-- return the number of bytes written.
+wordToAddrBE# :: Word# -> Addr# -> State# s -> (# State# s, Word# #)
+wordToAddrBE# w addr = go 0# (WORD_SIZE_IN_BITS# -# clz)
+ where
+ !clz = word2Int# (clz# w `and#` (not# 0b0111##)) -- keep complete bytes
+
+ go c sh s
+ | 0# <- sh
+ = (# s, int2Word# c #)
+
+ | True
+ , w' <- (w `uncheckedShiftRL#` (sh -# 8#)) `and#` 0xFF##
+ = case writeWord8OffAddr# addr c w' s of
+ s' -> go (c +# 1#) (sh -# 8#) s'
+
+-- | Write a Word to @/addr/@ in base-256 representation and
+-- return the number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: write most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+wordToAddr# :: Word# -> Addr# -> Bool# -> State# s -> (# State# s, Word# #)
+wordToAddr# a addr 0# s = wordToAddrLE# a addr s
+wordToAddr# a addr _ s = wordToAddrBE# a addr s
+
+
+-- | Read a Word from @/addr/@ in base-256 little-endian representation.
+--
+-- @'n' is the number of bytes to read.
+wordFromAddrLE# :: Word# -> Addr# -> State# s -> (# State# s, Word# #)
+wordFromAddrLE# n addr s
+ -- Optimize when we read a full word
+ | WORD_SIZE_IN_BYTES## <- n
+ = case readWordOffAddr# addr 0# s of
+#if defined(WORDS_BIGENDIAN)
+ (# s', w #) -> (# s', wordReverseBytes# w #)
+#else
+ (# s', w #) -> (# s', w #)
+#endif
+
+wordFromAddrLE# n addr s0 = go 0## 0# s0
+ where
+ go w c s
+ | isTrue# (c ==# word2Int# n)
+ = (# s, w #)
+
+ | True
+ = case readWord8OffAddr# addr c s of
+ (# s', b #) -> go (w `or#` (b `uncheckedShiftL#` (c `uncheckedIShiftL#` 3#)))
+ (c +# 1#)
+ s'
+
+-- | Read a Word from @/addr/@ in base-256 big-endian representation.
+--
+-- @'n' is the number of bytes to read.
+wordFromAddrBE# :: Word# -> Addr# -> State# s -> (# State# s, Word# #)
+wordFromAddrBE# n addr s
+ -- Optimize when we read a full word
+ | WORD_SIZE_IN_BYTES## <- n
+ = case readWordOffAddr# addr 0# s of
+#if defined(WORDS_BIGENDIAN)
+ (# s', w #) -> (# s', w #)
+#else
+ (# s', w #) -> (# s', wordReverseBytes# w #)
+#endif
+
+wordFromAddrBE# n addr s0 = go 0## 0# s0
+ where
+ go w c s
+ | isTrue# (c ==# word2Int# n)
+ = (# s, w #)
+
+ | True
+ = case readWord8OffAddr# addr c s of
+ (# s', b #) -> go ((w `uncheckedShiftL#` 8#) `or#` b)
+ (c +# 1#)
+ s'
+
+-- | Read a Word from @/addr/@ in base-256 representation.
+--
+-- @'n' is the number of bytes to read.
+--
+-- The endianness is selected with the Bool# parameter: write most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+wordFromAddr# :: Word# -> Addr# -> Bool# -> State# s -> (# State# s, Word# #)
+wordFromAddr# a addr 0# s = wordFromAddrLE# a addr s
+wordFromAddr# a addr _ s = wordFromAddrBE# a addr s
+
+
+
+-- | Write a full word with little-endian encoding
+wordWriteAddrLE# :: Word# -> Addr# -> State# s -> State# s
+wordWriteAddrLE# w addr = writeWordOffAddr# addr 0#
+#if defined(WORDS_BIGENDIAN)
+ (wordReverseBytes# w)
+#else
+ w
+#endif
+
+-- | Write a full word with little-endian encoding
+wordWriteAddrBE# :: Word# -> Addr# -> State# s -> State# s
+wordWriteAddrBE# w addr = writeWordOffAddr# addr 0#
+#if defined(WORDS_BIGENDIAN)
+ w
+#else
+ (wordReverseBytes# w)
+#endif
+
+-- | Write a Word to @/MutableByteArray/@ in base-256 little-endian
+-- representation and return the number of bytes written.
+--
+-- The offset is in bytes.
+wordToMutableByteArrayLE# :: Word# -> MutableByteArray# s -> Word# -> State# s -> (# State# s, Word# #)
+wordToMutableByteArrayLE# x mba off = go x 0#
+ where
+ go w c s
+ | 0## <- w
+ = (# s, int2Word# c #)
+
+ | True
+ = case writeWord8Array# mba (word2Int# off +# c) (w `and#` 0xFF##) s of
+ s' -> go (w `uncheckedShiftRL#` 8#) (c +# 1#) s'
+
+-- | Write a Word to @/MutableByteArray/@ in base-256 big-endian representation and
+-- return the number of bytes written.
+--
+-- The offset is in bytes.
+wordToMutableByteArrayBE# :: Word# -> MutableByteArray# s -> Word# -> State# s -> (# State# s, Word# #)
+wordToMutableByteArrayBE# w mba off = go 0# (WORD_SIZE_IN_BITS# -# clz)
+ where
+ !clz = word2Int# (clz# w `and#` (not# 0b0111##)) -- keep complete bytes
+
+ go c sh s
+ | 0# <- sh
+ = (# s, int2Word# c #)
+
+ | True
+ , w' <- (w `uncheckedShiftRL#` (sh -# 8#)) `and#` 0xFF##
+ = case writeWord8Array# mba (word2Int# off +# c) w' s of
+ s' -> go (c +# 1#) (sh -# 8#) s'
+
+-- | Write a Word to @/MutableByteArray/@ in base-256 representation and
+-- return the number of bytes written.
+--
+-- The endianness is selected with the Bool# parameter: write most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+--
+-- The offset is in bytes.
+wordToMutableByteArray# :: Word# -> MutableByteArray# s -> Word# -> Bool# -> State# s -> (# State# s, Word# #)
+wordToMutableByteArray# a mba off 0# s = wordToMutableByteArrayLE# a mba off s
+wordToMutableByteArray# a mba off _ s = wordToMutableByteArrayBE# a mba off s
+
+-- | Write a full word with little-endian encoding
+wordWriteMutableByteArrayLE# :: Word# -> MutableByteArray# s -> Word# -> State# s -> State# s
+wordWriteMutableByteArrayLE# w mba off = writeWord8ArrayAsWord# mba (word2Int# off)
+#if defined(WORDS_BIGENDIAN)
+ (wordReverseBytes# w)
+#else
+ w
+#endif
+
+-- | Write a full word with little-endian encoding
+wordWriteMutableByteArrayBE# :: Word# -> MutableByteArray# s -> Word# -> State# s -> State# s
+wordWriteMutableByteArrayBE# w mba off = writeWord8ArrayAsWord# mba (word2Int# off)
+#if defined(WORDS_BIGENDIAN)
+ w
+#else
+ (wordReverseBytes# w)
+#endif
+
+-- | Read a Word from @/ByteArray/@ in base-256 little-endian representation.
+--
+-- @'n' is the number of bytes to read.
+wordFromByteArrayLE# :: Word# -> ByteArray# -> Word# -> Word#
+wordFromByteArrayLE# n ba off =
+ case n of
+ -- Optimize when we read a full word
+ WORD_SIZE_IN_BYTES## -> case indexWord8ArrayAsWord# ba (word2Int# off) of
+#if defined(WORDS_BIGENDIAN)
+ w -> wordReverseBytes# w
+#else
+ w -> w
+#endif
+
+ _ -> let
+ go w c
+ | isTrue# (c ==# word2Int# n)
+ = w
+
+ | True
+ = case indexWord8Array# ba (word2Int# off +# c) of
+ b -> go (w `or#` (b `uncheckedShiftL#` (c `uncheckedIShiftL#` 3#)))
+ (c +# 1#)
+ in go 0## 0#
+
+-- | Read a Word from @/ByteArray/@ in base-256 big-endian representation.
+--
+-- @'n' is the number of bytes to read.
+wordFromByteArrayBE# :: Word# -> ByteArray# -> Word# -> Word#
+wordFromByteArrayBE# n ba off
+ -- Optimize when we read a full word
+ | WORD_SIZE_IN_BYTES## <- n
+ = case indexWord8ArrayAsWord# ba (word2Int# off) of
+#if defined(WORDS_BIGENDIAN)
+ w -> w
+#else
+ w -> wordReverseBytes# w
+#endif
+
+wordFromByteArrayBE# n ba off = go 0## 0#
+ where
+ go w c
+ | isTrue# (c ==# word2Int# n)
+ = w
+
+ | True
+ = case indexWord8Array# ba (word2Int# off +# c) of
+ b -> go ((w `uncheckedShiftL#` 8#) `or#` b) (c +# 1#)
+
+-- | Read a Word from @/ByteArray/@ in base-256 representation.
+--
+-- @'n' is the number of bytes to read.
+--
+-- The endianness is selected with the Bool# parameter: write most significant
+-- byte first (big-endian) if @1#@ or least significant byte first
+-- (little-endian) if @0#@.
+wordFromByteArray# :: Word# -> ByteArray# -> Word# -> Bool# -> Word#
+wordFromByteArray# a ba off 0# = wordFromByteArrayLE# a ba off
+wordFromByteArray# a ba off _ = wordFromByteArrayBE# a ba off
+
+----------------------------------
+-- IO
+----------------------------------
+
+ioVoid :: IO a -> State# RealWorld -> State# RealWorld
+ioVoid (IO io) s = case io s of
+ (# s', _ #) -> s'
+
+ioWord# :: IO Word -> State# RealWorld -> (# State# RealWorld, Word# #)
+ioWord# (IO io) s = case io s of
+ (# s', W# w #) -> (# s', w #)
+
+ioInt# :: IO Int -> State# RealWorld -> (# State# RealWorld, Int# #)
+ioInt# (IO io) s = case io s of
+ (# s', I# i #) -> (# s', i #)
+
+ioBool :: IO Bool -> State# RealWorld -> (# State# RealWorld, Bool# #)
+ioBool (IO io) s = case io s of
+ (# s', False #) -> (# s', 0# #)
+ (# s', True #) -> (# s', 1# #)
+
+
+----------------------------------
+-- Exception
+----------------------------------
+
+#if (__GLASGOW_HASKELL__ >= 811)
+
+underflow :: a
+underflow = raiseUnderflow# void#
+
+divByZero :: a
+divByZero = raiseDivZero# void#
+
+unexpectedValue :: a
+unexpectedValue = raiseOverflow# void#
+
+#else
+
+-- Before GHC 8.11 we use the exception trick taken from #14664
+exception :: a
+exception = runRW# \s ->
+ case atomicLoop s of
+ (# _, a #) -> a
+ where
+ atomicLoop s = atomically# atomicLoop s
+
+underflow :: a
+underflow = exception
+
+divByZero :: a
+divByZero = exception
+
+unexpectedValue :: a
+unexpectedValue = exception
+
+#endif
diff --git a/libraries/ghc-bignum/src/GHC/Num/WordArray.hs b/libraries/ghc-bignum/src/GHC/Num/WordArray.hs
new file mode 100644
index 0000000000..78c450b55e
--- /dev/null
+++ b/libraries/ghc-bignum/src/GHC/Num/WordArray.hs
@@ -0,0 +1,432 @@
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE MultiWayIf #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE PolyKinds #-}
+{-# LANGUAGE KindSignatures #-}
+{-# OPTIONS_GHC -Wno-name-shadowing #-}
+
+module GHC.Num.WordArray where
+
+import GHC.Prim
+import GHC.Magic
+import GHC.Types
+import GHC.Num.Primitives
+
+#include "MachDeps.h"
+#include "WordSize.h"
+
+default ()
+
+-- | Unlifted array of Word
+type WordArray# = ByteArray#
+type MutableWordArray# = MutableByteArray#
+
+data WordArray = WordArray WordArray#
+data MutableWordArray s = MutableWordArray (MutableWordArray# s)
+
+-- | Convert limb count into byte count
+wordsToBytes# :: Int# -> Int#
+wordsToBytes# i = i `uncheckedIShiftL#` WORD_SIZE_BYTES_SHIFT#
+
+-- | Convert byte count into limb count
+bytesToWords# :: Int# -> Int#
+bytesToWords# i = i `uncheckedIShiftRL#` WORD_SIZE_BYTES_SHIFT#
+
+
+-- | Create a new WordArray# of the given size (*in Word#*) and apply the
+-- action to it before returning it frozen
+withNewWordArray#
+ :: Int# -- ^ Size in Word
+ -> (MutableWordArray# RealWorld -> State# RealWorld -> State# RealWorld)
+ -> WordArray#
+withNewWordArray# sz act = case runRW# io of (# _, a #) -> a
+ where
+ io s =
+ case newWordArray# sz s of { (# s, mwa #) ->
+ case act mwa s of { s ->
+ unsafeFreezeByteArray# mwa s
+ }}
+
+-- | Create two new WordArray# of the given sizes (*in Word#*) and apply the
+-- action to them before returning them frozen
+withNewWordArray2#
+ :: Int# -- ^ Size in Word
+ -> Int# -- ^ Ditto
+ -> (MutableWordArray# RealWorld
+ -> MutableWordArray# RealWorld
+ -> State# RealWorld
+ -> State# RealWorld)
+ -> (# WordArray#, WordArray# #)
+withNewWordArray2# sz1 sz2 act = case runRW# io of (# _, a #) -> a
+ where
+ io s =
+ case newWordArray# sz1 s of { (# s, mwa1 #) ->
+ case newWordArray# sz2 s of { (# s, mwa2 #) ->
+ case act mwa1 mwa2 s of { s ->
+ case unsafeFreezeByteArray# mwa1 s of { (# s, wa1 #) ->
+ case unsafeFreezeByteArray# mwa2 s of { (# s, wa2 #) ->
+ (# s, (# wa1, wa2 #) #)
+ }}}}}
+
+-- | Create a new WordArray#
+newWordArray# :: Int# -> State# s -> (# State# s, MutableWordArray# s #)
+newWordArray# sz s = newByteArray# (wordsToBytes# sz) s
+
+-- | Create a new WordArray# of the given size (*in Word#*), apply the action to
+-- it, trim its most significant zeroes, then return it frozen
+withNewWordArrayTrimed#
+ :: Int# -- ^ Size in Word
+ -> (MutableWordArray# RealWorld -> State# RealWorld -> State# RealWorld)
+ -> WordArray#
+withNewWordArrayTrimed# sz act = withNewWordArray# sz \mwa s ->
+ case act mwa s of
+ s' -> mwaTrimZeroes# mwa s'
+
+-- | Create two new WordArray# of the given sizes (*in Word#*), apply the action
+-- to them, trim their most significant zeroes, then return them frozen
+withNewWordArray2Trimed#
+ :: Int# -- ^ Size in Word
+ -> Int# -- ^ Ditto
+ -> (MutableWordArray# RealWorld
+ -> MutableWordArray# RealWorld
+ -> State# RealWorld
+ -> State# RealWorld)
+ -> (# WordArray#, WordArray# #)
+withNewWordArray2Trimed# sz1 sz2 act = withNewWordArray2# sz1 sz2 \mwa1 mwa2 s ->
+ case act mwa1 mwa2 s of
+ s' -> case mwaTrimZeroes# mwa1 s' of
+ s'' -> mwaTrimZeroes# mwa2 s''
+
+-- | Create a new WordArray# of the given size (*in Word#*), apply the action to
+-- it. If the action returns true#, trim its most significant zeroes, then
+-- return it frozen. Otherwise, return ().
+withNewWordArrayTrimedMaybe#
+ :: Int# -- ^ Size in Word
+ -> (MutableWordArray# RealWorld -> State# RealWorld -> (# State# RealWorld, Bool# #))
+ -> (# () | WordArray# #)
+withNewWordArrayTrimedMaybe# sz act = case runRW# io of (# _, a #) -> a
+ where
+ io s =
+ case newWordArray# sz s of
+ (# s, mwa #) -> case act mwa s of
+ (# s, 0# #) -> (# s, (# () | #) #)
+ (# s, _ #) -> case mwaTrimZeroes# mwa s of
+ s -> case unsafeFreezeByteArray# mwa s of
+ (# s, ba #) -> (# s, (# | ba #) #)
+
+-- | Create a WordArray# from two Word#
+--
+-- `byteArrayFromWord2# msw lsw = lsw:msw`
+wordArrayFromWord2# :: Word# -> Word# -> WordArray#
+wordArrayFromWord2# msw lsw =
+ withNewWordArray# 2# \mwa s ->
+ case mwaWrite# mwa 0# lsw s of
+ s -> mwaWrite# mwa 1# msw s
+
+-- | Create a WordArray# from one Word#
+wordArrayFromWord# :: Word# -> WordArray#
+wordArrayFromWord# w =
+ withNewWordArray# 1# \mwa s ->
+ mwaWrite# mwa 0# w s
+
+-- | Word array size
+wordArraySize# :: WordArray# -> Int#
+wordArraySize# ba = bytesToWords# (sizeofByteArray# ba)
+
+
+-- | Equality test for WordArray#
+
+-- | Get size in Words
+mwaSize# :: MutableWordArray# s-> State# s -> (# State# s, Int# #)
+mwaSize# mba s = case getSizeofMutableByteArray# mba s of
+ (# s2, sz #) -> (# s2, bytesToWords# sz #)
+
+-- | Get the last Word (must be non empty!)
+wordArrayLast# :: WordArray# -> Word#
+wordArrayLast# a = indexWordArray# a (wordArraySize# a -# 1#)
+
+-- | Copy Words from a WordArray
+--
+-- Don't do anything if the number of words to copy is <= 0
+mwaArrayCopy# :: MutableByteArray# s -> Int# -> WordArray# -> Int# -> Int# -> State# s -> State# s
+mwaArrayCopy# dst dstIdx src srcIdx n s
+ | isTrue# (n <=# 0#) = s
+ | True = copyByteArray#
+ src (wordsToBytes# srcIdx)
+ dst (wordsToBytes# dstIdx)
+ (wordsToBytes# n) s
+
+-- | Shrink last words of a WordArray
+mwaShrink# :: MutableByteArray# s -> Int# -> State# s -> State# s
+mwaShrink# _mwa 0# s = s
+mwaShrink# mwa i s =
+ case mwaSize# mwa s of
+ (# s, n #) -> shrinkMutableByteArray# mwa (wordsToBytes# (n -# i)) s
+
+-- | Set size
+mwaSetSize# :: MutableByteArray# s -> Int# -> State# s -> State# s
+mwaSetSize# mwa n s = shrinkMutableByteArray# mwa (wordsToBytes# n) s
+
+-- | Copy the WordArray into the MWA and shrink the size of MWA to the one of
+-- the WordArray
+mwaInitCopyShrink# :: MutableByteArray# s -> WordArray# -> State# s -> State# s
+mwaInitCopyShrink# mwa wa s =
+ case mwaArrayCopy# mwa 0# wa 0# (wordArraySize# wa) s of
+ s -> mwaSetSize# mwa (wordArraySize# wa) s
+
+-- | Trim ending zeroes
+mwaTrimZeroes# :: MutableByteArray# s -> State# s -> State# s
+mwaTrimZeroes# mwa s1 =
+ case mwaClz mwa s1 of
+ (# s2, 0# #) -> s2
+ (# s2, c #) -> mwaShrink# mwa c s2
+
+-- | Count leading zero Words
+mwaClz :: MutableWordArray# s -> State# s -> (# State# s, Int# #)
+mwaClz mwa s1 = case mwaSize# mwa s1 of
+ (# s2,sz #) -> mwaClzAt mwa (sz -# 1#) s2
+
+-- | Count leading zero Words starting at given position
+mwaClzAt :: MutableWordArray# s -> Int# -> State# s -> (# State# s, Int# #)
+mwaClzAt mwa = go 0#
+ where
+ go c i s
+ | isTrue# (i <# 0#) = (# s, c #)
+ | True = case readWordArray# mwa i s of
+ (# s', 0## #) -> go (c +# 1#) (i -# 1#) s'
+ (# s', _ #) -> (# s', c #)
+
+-- | Count leading zero Words starting at given position
+waClzAt :: WordArray# -> Int# -> Int#
+waClzAt wa = go 0#
+ where
+ go c i
+ | isTrue# (i <# 0#)
+ = c
+
+ | 0## <- indexWordArray# wa i
+ = go (c +# 1#) (i -# 1#)
+
+ | True
+ = c
+
+-- | Compare the most signiciant limbs of a and b. The comparison stops (i.e.
+-- returns EQ) when there isn't enough lims in a or b to perform another
+-- comparison.
+wordArrayCompareMSWords :: WordArray# -> WordArray# -> Ordering
+wordArrayCompareMSWords wa wb
+ | 0# <- szA
+ , 0# <- szB
+ = EQ
+
+ | 0# <- szA
+ = LT
+
+ | 0# <- szB
+ = GT
+
+ | True
+ = go (szA -# 1#) (szB -# 1#)
+ where
+ szA = wordArraySize# wa
+ szB = wordArraySize# wb
+
+ go i j
+ | isTrue# (i <# 0#) = EQ
+ | isTrue# (j <# 0#) = EQ
+ | True =
+ let
+ a = indexWordArray# wa i
+ b = indexWordArray# wb j
+ in if | isTrue# (a `gtWord#` b) -> GT
+ | isTrue# (b `gtWord#` a) -> LT
+ | True -> go (i -# 1#) (j -# 1#)
+
+
+-- | Compute MutableWordArray <- WordArray + Word
+--
+-- The MutableWordArray may not be initialized and will be erased anyway.
+--
+-- Input: Size(MutableWordArray) = Size(WordArray) + 1
+-- Output: Size(MutableWordArray) = Size(WordArray) [+ 1]
+mwaInitArrayPlusWord :: MutableWordArray# s -> WordArray# -> Word# -> State# s -> State#s
+mwaInitArrayPlusWord mwa wa = go 0#
+ where
+ sz = wordArraySize# wa
+ go i carry s
+ | isTrue# (i ># sz) = s
+ | isTrue# (i ==# sz) = mwaWriteOrShrink mwa carry i s
+ | 0## <- carry = -- copy higher remaining words and shrink the mwa
+ case mwaArrayCopy# mwa i wa i (sz -# i) s of
+ s2 -> mwaShrink# mwa 1# s2
+ | True = let !(# l,c #) = addWordC# (indexWordArray# wa i) carry
+ in case mwaWrite# mwa i l s of
+ s2 -> go (i +# 1#) (int2Word# c) s2
+
+-- | Write the most-significant Word:
+-- * if it is 0: shrink the array of 1 Word
+-- * otherwise: write it
+mwaWriteOrShrink :: MutableWordArray# s -> Word# -> Int# -> State# s -> State# s
+mwaWriteOrShrink mwa 0## _i s = mwaShrink# mwa 1# s
+mwaWriteOrShrink mwa w i s = mwaWrite# mwa i w s
+
+-- | Compute the index of the most-significant Word and write it.
+mwaWriteMostSignificant :: MutableWordArray# s -> Word# -> State# s -> State# s
+mwaWriteMostSignificant mwa w s =
+ case mwaSize# mwa s of
+ (# s', sz #) -> mwaWriteOrShrink mwa w (sz -# 1#) s'
+
+-- | MutableWordArray <- zipWith op wa1 wa2
+--
+-- Required output: Size(MutableWordArray) = min Size(wa1) Size(wa2)
+mwaInitArrayBinOp :: MutableWordArray# s -> WordArray# -> WordArray# -> (Word# -> Word# -> Word#) -> State# s -> State#s
+mwaInitArrayBinOp mwa wa wb op s = go 0# s
+ where
+ !sz = minI# (wordArraySize# wa) (wordArraySize# wb)
+ go i s'
+ | isTrue# (i ==# sz) = s'
+ | True =
+ case indexWordArray# wa i `op` indexWordArray# wb i of
+ v -> case mwaWrite# mwa i v s' of
+ s'' -> go (i +# 1#) s''
+
+-- | Write an element of the MutableWordArray
+mwaWrite# :: MutableWordArray# s -> Int# -> Word# -> State# s -> State# s
+mwaWrite# = writeWordArray#
+
+-- | Fill some part of a MutableWordArray with the given Word#
+mwaFill# :: MutableWordArray# s -> Word# -> Word# -> Word# -> State# s -> State# s
+mwaFill# _ _ _ 0## s = s
+mwaFill# mwa v off n s = case mwaWrite# mwa (word2Int# off) v s of
+ s' -> mwaFill# mwa v (off `plusWord#` 1##) (n `minusWord#` 1##) s'
+
+-- | Add Word# inplace (a the specified offset) in the mwa with carry propagation.
+mwaAddInplaceWord# :: MutableWordArray# d -> Int# -> Word# -> State# d -> State# d
+mwaAddInplaceWord# _ _ 0## s = s
+mwaAddInplaceWord# mwa i y s = case readWordArray# mwa i s of
+ (# s1, x #) -> let !(# h,l #) = plusWord2# x y
+ in case mwaWrite# mwa i l s1 of
+ s2 -> mwaAddInplaceWord# mwa (i +# 1#) h s2
+
+-- | Sub Word# inplace (at the specified offset) in the mwa with carry
+-- propagation.
+--
+-- Return True# on overflow
+mwaSubInplaceWord#
+ :: MutableWordArray# d
+ -> Int#
+ -> Word#
+ -> State# d
+ -> (# State# d, Bool# #)
+mwaSubInplaceWord# mwa ii iw s1 = case mwaSize# mwa s1 of
+ (# is, sz #) ->
+ let
+ go _ 0## s = (# s, 0# #) -- no overflow
+ go i y s
+ | isTrue# (i >=# sz) = (# s, 1# #) -- overflow
+ | True = case readWordArray# mwa i s of
+ (# s1, x #) -> let !(# l,h #) = subWordC# x y
+ in case mwaWrite# mwa i l s1 of
+ s2 -> go (i +# 1#) (int2Word# h) s2
+ in go ii iw is
+
+
+-- | Trim `a` of `k` less significant limbs and then compare the result with `b`
+--
+-- "mwa" doesn't need to be trimmed
+mwaTrimCompare :: Int# -> MutableWordArray# s -> WordArray# -> State# s -> (# State# s, Ordering #)
+mwaTrimCompare k mwa wb s1
+ | (# s, szA #) <- mwaSize# mwa s1
+ , szB <- wordArraySize# wb
+ =
+ let
+ go i s
+ | isTrue# (i <# 0#) = (# s, EQ #)
+ | True = case readWordArray# mwa (i +# k) s of
+ (# s2, ai #) ->
+ let bi = if isTrue# (i >=# szB)
+ then 0##
+ else indexWordArray# wb i
+ in if | isTrue# (ai `gtWord#` bi) -> (# s2, GT #)
+ | isTrue# (bi `gtWord#` ai) -> (# s2, LT #)
+ | True -> go (i -# 1#) s2
+
+ szTrimA = szA -# k
+
+ in if | isTrue# (szTrimA <# szB) -> (# s, LT #)
+ | True -> go (szA -# k -# 1#) s
+
+
+-- | Sub array inplace (at the specified offset) in the mwa with carry propagation.
+--
+-- We don't trim the resulting array!
+--
+-- Return True# on overflow.
+mwaSubInplaceArray :: MutableWordArray# d -> Int# -> WordArray# -> State# d -> (# State# d, Bool# #)
+mwaSubInplaceArray mwa off wb = go (wordArraySize# wb -# 1#)
+ where
+ go i s
+ | isTrue# (i <# 0#) = (# s, 0# #) -- no overflow
+ | True
+ = case mwaSubInplaceWord# mwa (off +# i) (indexWordArray# wb i) s of
+ (# s2, 0# #) -> go (i -# 1#) s2
+ (# s2, _ #) -> (# s2, 1# #) -- overflow
+
+-- | Add array inplace (a the specified offset) in the mwa with carry propagation.
+--
+-- Upper bound of the result mutable aray is not checked against overflow.
+mwaAddInplaceArray :: MutableWordArray# d -> Int# -> WordArray# -> State# d -> State# d
+mwaAddInplaceArray mwa off wb = go 0# 0##
+ where
+ !maxi = wordArraySize# wb
+ go i c s
+ | isTrue# (i ==# maxi) = mwaAddInplaceWord# mwa (i +# off) c s
+ | True
+ = case readWordArray# mwa (i +# off) s of
+ (# s, v #) -> case plusWord3# v (indexWordArray# wb i) c of
+ (# c', v' #) -> case writeWordArray# mwa (i +# off) v' s of
+ s -> go (i +# 1#) c' s
+
+-- | Sub array inplace (at the specified offset) in the mwa with carry propagation.
+--
+-- We don't trim the resulting array!
+--
+-- Return True# on overflow.
+mwaSubInplaceMutableArray :: MutableWordArray# d -> Int# -> MutableWordArray# d -> State# d -> (# State# d, Bool# #)
+mwaSubInplaceMutableArray mwa off mwb s0 =
+ case mwaSize# mwb s0 of
+ (# s1, szB #) -> go (szB -# 1#) s1
+ where
+ go i s
+ | isTrue# (i <# 0#) = (# s, 0# #) -- no overflow
+ | True
+ = case readWordArray# mwb i s of
+ (# s1, bi #) -> case mwaSubInplaceWord# mwa (off +# i) bi s1 of
+ (# s2, 0# #) -> go (i -# 1#) s2
+ (# s2, _ #) -> (# s2, 1# #) -- overflow
+
+-- | Sub an array inplace and then trim zeroes
+--
+-- Don't check overflow. The caller must ensure that a>=b
+mwaSubInplaceArrayTrim :: MutableWordArray# d -> Int# -> WordArray# -> State# d -> State# d
+mwaSubInplaceArrayTrim mwa off wb s =
+ case mwaSubInplaceArray mwa off wb s of
+ (# s', _ #) -> mwaTrimZeroes# mwa s'
+
+
+-- | Read an indexed Word in the MutableWordArray. If the index is out-of-bound,
+-- return zero.
+mwaReadOrZero :: MutableWordArray# s -> Int# -> State# s -> (# State# s, Word# #)
+mwaReadOrZero mwa i s = case mwaSize# mwa s of
+ (# s2, sz #)
+ | isTrue# (i >=# sz) -> (# s2, 0## #)
+ | isTrue# (i <# 0#) -> (# s2, 0## #)
+ | True -> readWordArray# mwa i s2
+
+mwaRead# :: MutableWordArray# s -> Int# -> State# s -> (# State# s, Word# #)
+mwaRead# = readWordArray#