libmpdec
========
libmpdec is a fast C/C++ library for correctly-rounded arbitrary precision
decimal floating point arithmetic. It is a complete implementation of
Mike Cowlishaw/IBM's General Decimal Arithmetic Specification.
Files required for the Python _decimal module
=============================================
 Core files for small and medium precision arithmetic
 ----------------------------------------------------
 basearith.{c,h} -> Core arithmetic in base 10**9 or 10**19.
 bits.h -> Portable detection of least/most significant one-bit.
 constants.{c,h} -> Constants that are used in multiple files.
 context.c -> Context functions.
 io.{c,h} -> Conversions between mpd_t and ASCII strings,
 mpd_t formatting (allows UTF-8 fill character).
 memory.{c,h} -> Allocation handlers with overflow detection
 and functions for switching between static
 and dynamic mpd_t.
 mpdecimal.{c,h} -> All (quiet) functions of the specification.
 typearith.h -> Fast primitives for double word multiplication,
 division etc.
 Visual Studio only:
 ~~~~~~~~~~~~~~~~~~~
 vccompat.h -> snprintf <==> sprintf_s and similar things.
 vcstdint.h -> stdint.h (included in VS 2010 but not in VS 2008).
 vcdiv64.asm -> Double word division used in typearith.h. VS 2008 does
 not allow inline asm for x64. Also, it does not provide
 an intrinsic for double word division.
 Files for bignum arithmetic:
 ----------------------------
 The following files implement the Fast Number Theoretic Transform
 used for multiplying coefficients with more than 1024 words (see
 mpdecimal.c: _mpd_fntmul()).
 umodarith.h -> Fast low level routines for unsigned modular arithmetic.
 numbertheory.{c,h} -> Routines for setting up the Number Theoretic Transform.
 difradix2.{c,h} -> Decimation in frequency transform, used as the
 "base case" by the following three files:
 fnt.{c,h} -> Transform arrays up to 4096 words.
 sixstep.{c,h} -> Transform larger arrays of length 2**n.
 fourstep.{c,h} -> Transform larger arrays of length 3 * 2**n.
 convolute.{c,h} -> Fast convolution using one of the three transform
 functions.
 transpose.{c,h} -> Transpositions needed for the sixstep algorithm.
 crt.{c,h} -> Chinese Remainder Theorem: use information from three
 transforms modulo three different primes to get the
 final result.
Pointers to literature, proofs and more
=======================================
 literature/
 -----------
 REFERENCES.txt -> List of relevant papers.
 bignum.txt -> Explanation of the Fast Number Theoretic Transform (FNT).
 fnt.py -> Verify constants used in the FNT; Python demo for the
 O(N**2) discrete transform.
 matrix-transform.txt -> Proof for the Matrix Fourier Transform used in
 fourstep.c.
 six-step.txt -> Show that the algorithm used in sixstep.c is
 a variant of the Matrix Fourier Transform.
 mulmod-64.txt -> Proof for the mulmod64 algorithm from
 umodarith.h.
 mulmod-ppro.txt -> Proof for the x87 FPU modular multiplication
 from umodarith.h.
 umodarith.lisp -> ACL2 proofs for many functions from umodarith.h.
Library Author
==============
 Stefan Krah <skrah@bytereef.org>