diff --git a/Data/Double/Conversion/ByteString.hs b/Data/Double/Conversion/ByteString.hs --- a/Data/Double/Conversion/ByteString.hs +++ b/Data/Double/Conversion/ByteString.hs @@ -3,7 +3,7 @@ -- Copyright : (c) 2011 MailRank, Inc. -- -- License : BSD-style --- Maintainer : bos@mailrank.com +-- Maintainer : bos@serpentine.com -- Stability : experimental -- Portability : GHC -- diff --git a/Data/Double/Conversion/FFI.hs b/Data/Double/Conversion/FFI.hs --- a/Data/Double/Conversion/FFI.hs +++ b/Data/Double/Conversion/FFI.hs @@ -1,11 +1,11 @@ -{-# LANGUAGE ForeignFunctionInterface, MagicHash, UnliftedFFITypes #-} +{-# LANGUAGE CPP, ForeignFunctionInterface, MagicHash, UnliftedFFITypes #-} -- | -- Module : Data.Double.Conversion.FFI -- Copyright : (c) 2011 MailRank, Inc. -- -- License : BSD-style --- Maintainer : bos@mailrank.com +-- Maintainer : bos@serpentine.com -- Stability : experimental -- Portability : GHC -- @@ -29,7 +29,11 @@ ) where import Data.Word (Word8) +#if __GLASGOW_HASKELL__ >= 703 +import Foreign.C.Types (CDouble(CDouble), CInt(CInt)) +#else import Foreign.C.Types (CDouble, CInt) +#endif import Foreign.Ptr (Ptr) import GHC.Prim (MutableByteArray#) diff --git a/Data/Double/Conversion/Text.hs b/Data/Double/Conversion/Text.hs --- a/Data/Double/Conversion/Text.hs +++ b/Data/Double/Conversion/Text.hs @@ -5,7 +5,7 @@ -- Copyright : (c) 2011 MailRank, Inc. -- -- License : BSD-style --- Maintainer : bos@mailrank.com +-- Maintainer : bos@serpentine.com -- Stability : experimental -- Portability : GHC -- diff --git a/README.markdown b/README.markdown --- a/README.markdown +++ b/README.markdown @@ -11,11 +11,11 @@ and other improvements. Please report bugs via the -[github issue tracker](https://github.com/mailrank/double-conversion/issues). +[github issue tracker](https://github.com/bos/double-conversion/issues). -Master [git repository](https://github.com/mailrank/double-conversion): +Master [git repository](https://github.com/bos/double-conversion): -* `git clone git://github.com/mailrank/double-conversion.git` +* `git clone git://github.com/bos/double-conversion.git` There's also a [Mercurial mirror](https://bitbucket.org/bos/double-conversion): @@ -27,4 +27,4 @@ ------- This library is written and maintained by Bryan O'Sullivan, -. +. diff --git a/double-conversion.cabal b/double-conversion.cabal --- a/double-conversion.cabal +++ b/double-conversion.cabal @@ -1,12 +1,12 @@ name: double-conversion -version: 0.2.0.1 +version: 0.2.0.3 license: BSD3 license-file: LICENSE -homepage: https://github.com/mailrank/double-conversion -bug-reports: https://github.com/mailrank/double-conversion/issues +homepage: https://github.com/bos/double-conversion +bug-reports: https://github.com/bos/double-conversion/issues category: Text -author: Bryan O'Sullivan -maintainer: Bryan O'Sullivan +author: Bryan O'Sullivan +maintainer: Bryan O'Sullivan stability: experimental tested-with: GHC == 7.0.3 synopsis: Fast conversion between double precision floating point and text @@ -46,7 +46,6 @@ double-conversion/test/cctest/*.h double-conversion/test/cctest/SConscript include/*.h - tests/*.cabal tests/*.hs flag developer @@ -100,9 +99,22 @@ if impl(ghc >= 6.9) && impl(ghc < 6.11) build-depends: integer >= 0.1 && < 0.2 +test-suite tests + type: exitcode-stdio-1.0 + hs-source-dirs: tests + main-is: Properties.hs + ghc-options: -Wall + build-depends: + base, + bytestring, + double-conversion, + test-framework, + test-framework-quickcheck2, + text + source-repository head type: git - location: https://github.com/mailrank/double-conversion + location: https://github.com/bos/double-conversion source-repository head type: mercurial diff --git a/double-conversion/src/fast-dtoa.cc b/double-conversion/src/fast-dtoa.cc --- a/double-conversion/src/fast-dtoa.cc +++ b/double-conversion/src/fast-dtoa.cc @@ -31,6 +31,8 @@ #include "diy-fp.h" #include "double.h" +#include + namespace double_conversion { // The minimal and maximal target exponent define the range of w's binary @@ -222,121 +224,42 @@ return false; } - -static const uint32_t kTen4 = 10000; -static const uint32_t kTen5 = 100000; -static const uint32_t kTen6 = 1000000; -static const uint32_t kTen7 = 10000000; -static const uint32_t kTen8 = 100000000; -static const uint32_t kTen9 = 1000000000; - // Returns the biggest power of ten that is less than or equal to the given // number. We furthermore receive the maximum number of bits 'number' has. -// If number_bits == 0 then 0^-1 is returned +// +// Returns power == 10^(exponent_plus_one-1) such that +// power <= number < power * 10. +// If number_bits == 0 then 0^(0-1) is returned. // The number of bits must be <= 32. // Precondition: number < (1 << (number_bits + 1)). + +// Inspired by the method for finding an integer log base 10 from here: +// http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10 +static unsigned int const kSmallPowersOfTen[] = + {0, 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, + 1000000000}; + static void BiggestPowerTen(uint32_t number, int number_bits, uint32_t* power, - int* exponent) { + int* exponent_plus_one) { ASSERT(number < (1 << (number_bits + 1))); - - switch (number_bits) { - case 32: - case 31: - case 30: - if (kTen9 <= number) { - *power = kTen9; - *exponent = 9; - break; - } // else fallthrough - case 29: - case 28: - case 27: - if (kTen8 <= number) { - *power = kTen8; - *exponent = 8; - break; - } // else fallthrough - case 26: - case 25: - case 24: - if (kTen7 <= number) { - *power = kTen7; - *exponent = 7; - break; - } // else fallthrough - case 23: - case 22: - case 21: - case 20: - if (kTen6 <= number) { - *power = kTen6; - *exponent = 6; - break; - } // else fallthrough - case 19: - case 18: - case 17: - if (kTen5 <= number) { - *power = kTen5; - *exponent = 5; - break; - } // else fallthrough - case 16: - case 15: - case 14: - if (kTen4 <= number) { - *power = kTen4; - *exponent = 4; - break; - } // else fallthrough - case 13: - case 12: - case 11: - case 10: - if (1000 <= number) { - *power = 1000; - *exponent = 3; - break; - } // else fallthrough - case 9: - case 8: - case 7: - if (100 <= number) { - *power = 100; - *exponent = 2; - break; - } // else fallthrough - case 6: - case 5: - case 4: - if (10 <= number) { - *power = 10; - *exponent = 1; - break; - } // else fallthrough - case 3: - case 2: - case 1: - if (1 <= number) { - *power = 1; - *exponent = 0; - break; - } // else fallthrough - case 0: - *power = 0; - *exponent = -1; - break; - default: - // Following assignments are here to silence compiler warnings. - *power = 0; - *exponent = 0; - UNREACHABLE(); + // 1233/4096 is approximately 1/lg(10). + int exponent_plus_one_guess = ((number_bits + 1) * 1233 >> 12); + // We increment to skip over the first entry in the kPowersOf10 table. + // Note: kPowersOf10[i] == 10^(i-1). + exponent_plus_one_guess++; + // We don't have any guarantees that 2^number_bits <= number. + // TODO(floitsch): can we change the 'while' into an 'if'? We definitely see + // number < (2^number_bits - 1), but I haven't encountered + // number < (2^number_bits - 2) yet. + while (number < kSmallPowersOfTen[exponent_plus_one_guess]) { + exponent_plus_one_guess--; } + *power = kSmallPowersOfTen[exponent_plus_one_guess]; + *exponent_plus_one = exponent_plus_one_guess; } - // Generates the digits of input number w. // w is a floating-point number (DiyFp), consisting of a significand and an // exponent. Its exponent is bounded by kMinimalTargetExponent and @@ -418,10 +341,10 @@ // Modulo by one is an and. uint64_t fractionals = too_high.f() & (one.f() - 1); uint32_t divisor; - int divisor_exponent; + int divisor_exponent_plus_one; BiggestPowerTen(integrals, DiyFp::kSignificandSize - (-one.e()), - &divisor, &divisor_exponent); - *kappa = divisor_exponent + 1; + &divisor, &divisor_exponent_plus_one); + *kappa = divisor_exponent_plus_one; *length = 0; // Loop invariant: buffer = too_high / 10^kappa (integer division) // The invariant holds for the first iteration: kappa has been initialized @@ -526,10 +449,10 @@ // Modulo by one is an and. uint64_t fractionals = w.f() & (one.f() - 1); uint32_t divisor; - int divisor_exponent; + int divisor_exponent_plus_one; BiggestPowerTen(integrals, DiyFp::kSignificandSize - (-one.e()), - &divisor, &divisor_exponent); - *kappa = divisor_exponent + 1; + &divisor, &divisor_exponent_plus_one); + *kappa = divisor_exponent_plus_one; *length = 0; // Loop invariant: buffer = w / 10^kappa (integer division) diff --git a/tests/Properties.hs b/tests/Properties.hs --- a/tests/Properties.hs +++ b/tests/Properties.hs @@ -1,11 +1,19 @@ -import Data.Double.Conversion -import Test.QuickCheck -import Test.Framework (defaultMain, testGroup) +import Test.Framework (defaultMain) import Test.Framework.Providers.QuickCheck2 (testProperty) +import qualified Data.ByteString.Char8 as B +import qualified Data.Double.Conversion.ByteString as B +import qualified Data.Double.Conversion.Text as T import qualified Data.Text as T -shortest a = (read . T.unpack . toShortest) a == a +shortest :: (Double -> String) -> Double -> Double -> Bool +shortest f a b = case read (f ab) of + ba | isNaN ba -> isNaN ab + | isInfinite ba -> isInfinite ab && signum ba == signum ab + | otherwise -> ba == ab + where ab = a / b +main :: IO () main = defaultMain [ - testProperty "shortest" shortest + testProperty "b_shortest" $ shortest (B.unpack . B.toShortest) + , testProperty "t_shortest" $ shortest (T.unpack . T.toShortest) ] diff --git a/tests/double-conversion-tests.cabal b/tests/double-conversion-tests.cabal deleted file mode 100644 --- a/tests/double-conversion-tests.cabal +++ /dev/null @@ -1,15 +0,0 @@ -name: double-conversion-tests -version: 0 -cabal-version: >= 1.8 -build-type: Simple - -executable qc - main-is: Properties.hs - - build-depends: - QuickCheck, - base, - double-conversion, - test-framework, - test-framework-quickcheck2, - text >= 0.11.0.8