{-# LANGUAGE Trustworthy #-}{-# LANGUAGE CPP, MagicHash, UnboxedTuples, NoImplicitPrelude #-}{-# OPTIONS_GHC -O2 #-}{-# OPTIONS_HADDOCK not-home #-}------------------------------------------------------------------------------- |-- Module : GHC.Float.ConversionUtils-- Copyright : (c) Daniel Fischer 2010-- License : see libraries/base/LICENSE---- Maintainer : cvs-ghc@haskell.org-- Stability : internal-- Portability : non-portable (GHC Extensions)---- Utilities for conversion between Double/Float and Rational-------------------------------------------------------------------------------
#include "MachDeps.h"
moduleGHC.Float.ConversionUtils(elimZerosInteger ,elimZerosInt# )whereimportGHC.Base importGHC.Integer
#if WORD_SIZE_IN_BITS < 64
importGHC.IntWord64
#endif
default()
#if WORD_SIZE_IN_BITS < 64

#define TO64 integerToInt64
toByte64#::Int64#->Int#toByte64#i=word2Int#(and#255##(int2Word#(int64ToInt#i)))-- Double mantissae have 53 bits, too much for Int#elim64#::Int64#->Int#->(#Integer,Int##)elim64#ne=casezeroCount(toByte64#n)oft|isTrue#(e<=#t)->(#int64ToInteger(uncheckedIShiftRA64#ne),0##)|isTrue#(t<#8#)->(#int64ToInteger(uncheckedIShiftRA64#nt),e-#t#)|otherwise->elim64#(uncheckedIShiftRA64#n8#)(e-#8#)
#else

#define TO64 integerToInt
-- Double mantissae fit it Int#elim64# ::Int#->Int#->(#Integer,Int##)elim64# :: Int# -> Int# -> (# Integer, Int# #)
elim64# =Int# -> Int# -> (# Integer, Int# #)
elimZerosInt# 
#endif
{-# INLINEelimZerosInteger #-}elimZerosInteger ::Integer->Int#->(#Integer,Int##)elimZerosInteger :: Integer -> Int# -> (# Integer, Int# #)
elimZerosInteger m :: Integer
m e :: Int#
e =Int# -> Int# -> (# Integer, Int# #)
elim64# (TO64m)eelimZerosInt# ::Int#->Int#->(#Integer,Int##)elimZerosInt# :: Int# -> Int# -> (# Integer, Int# #)
elimZerosInt# n :: Int#
n e :: Int#
e =caseInt# -> Int#
zeroCount (Int# -> Int#
toByte# Int#
n )oft :: Int#
t |Int# -> Bool
isTrue#(Int#
e Int# -> Int# -> Int#
<=#Int#
t )->(#Int# -> Integer
smallInteger(Int# -> Int# -> Int#
uncheckedIShiftRA#Int#
n Int#
e ),0##)|Int# -> Bool
isTrue#(Int#
t Int# -> Int# -> Int#
<#8#)->(#Int# -> Integer
smallInteger(Int# -> Int# -> Int#
uncheckedIShiftRA#Int#
n Int#
t ),Int#
e Int# -> Int# -> Int#
-#Int#
t #)|Bool
otherwise ->Int# -> Int# -> (# Integer, Int# #)
elimZerosInt# (Int# -> Int# -> Int#
uncheckedIShiftRA#Int#
n 8#)(Int#
e Int# -> Int# -> Int#
-#8#){-# INLINEzeroCount #-}zeroCount ::Int#->Int#zeroCount :: Int# -> Int#
zeroCount i :: Int#
i =caseBA
zeroCountArr ofBA ba :: ByteArray#
ba ->ByteArray# -> Int# -> Int#
indexInt8Array#ByteArray#
ba Int#
i toByte# ::Int#->Int#toByte# :: Int# -> Int#
toByte# i :: Int#
i =Word# -> Int#
word2Int#(Word# -> Word# -> Word#
and#255##(Int# -> Word#
int2Word#Int#
i ))dataBA =BA ByteArray#-- Number of trailing zero bits in a bytezeroCountArr ::BA zeroCountArr :: BA
zeroCountArr =letmkArr :: State# d -> ByteArray#
mkArr s :: State# d
s =caseInt# -> State# d -> (# State# d, MutableByteArray# d #)
forall d. Int# -> State# d -> (# State# d, MutableByteArray# d #)
newByteArray#256#State# d
s of(#s1 :: State# d
s1 ,mba :: MutableByteArray# d
mba #)->caseMutableByteArray# d -> Int# -> Int# -> State# d -> State# d
forall d.
MutableByteArray# d -> Int# -> Int# -> State# d -> State# d
writeInt8Array#MutableByteArray# d
mba 0#8#State# d
s1 ofs2 :: State# d
s2 ->letfillA :: Int# -> Int# -> Int# -> State# d -> State# d
fillA step :: Int#
step val :: Int#
val idx :: Int#
idx st :: State# d
st |Int# -> Bool
isTrue#(Int#
idx Int# -> Int# -> Int#
<#256#)=caseMutableByteArray# d -> Int# -> Int# -> State# d -> State# d
forall d.
MutableByteArray# d -> Int# -> Int# -> State# d -> State# d
writeInt8Array#MutableByteArray# d
mba Int#
idx Int#
val State# d
st ofnx :: State# d
nx ->Int# -> Int# -> Int# -> State# d -> State# d
fillA Int#
step Int#
val (Int#
idx Int# -> Int# -> Int#
+#Int#
step )State# d
nx |Int# -> Bool
isTrue#(Int#
step Int# -> Int# -> Int#
<#256#)=Int# -> Int# -> Int# -> State# d -> State# d
fillA (2#Int# -> Int# -> Int#
*#Int#
step )(Int#
val Int# -> Int# -> Int#
+#1#)Int#
step State# d
st |Bool
otherwise =State# d
st incaseInt# -> Int# -> Int# -> State# d -> State# d
fillA 2#0#1#State# d
s2 ofs3 :: State# d
s3 ->caseMutableByteArray# d -> State# d -> (# State# d, ByteArray# #)
forall d.
MutableByteArray# d -> State# d -> (# State# d, ByteArray# #)
unsafeFreezeByteArray#MutableByteArray# d
mba State# d
s3 of(#_,ba :: ByteArray#
ba #)->ByteArray#
ba incaseState# RealWorld -> ByteArray#
forall d. State# d -> ByteArray#
mkArr State# RealWorld
realWorld#ofb :: ByteArray#
b ->ByteArray# -> BA
BA ByteArray#
b