From 47afc1720d92cbf4c491d09506aeeb94ce4d874e Mon Sep 17 00:00:00 2001
From: Vincent Hanquez <vincent@snarc.org>
Date: Mon, 11 May 2015 07:10:15 +0100
Subject: [PATCH] [number] remove gcde_binary

---
 Crypto/Number/Basic.hs | 31 -------------------------------
 1 file changed, 31 deletions(-)

diff --git a/Crypto/Number/Basic.hs b/Crypto/Number/Basic.hs
index 618e7e9..0d79e55 100644
--- a/Crypto/Number/Basic.hs
+++ b/Crypto/Number/Basic.hs
@@ -19,7 +19,6 @@
 module Crypto.Number.Basic
     ( sqrti
     , gcde
-    , gcde_binary
     , areEven
     , log2
     ) where
@@ -84,36 +83,6 @@ gcde a b = if d < 0 then (-x,-y,-d) else (x,y,d) where
         f t (r, sa - (q * sb), ta - (q * tb))
 #endif
 
--- | get the extended GCD of two integer using the extended binary algorithm (HAC 14.61)
--- get (x,y,d) where d = gcd(a,b) and x,y satisfying ax + by = d
-gcde_binary :: Integer -> Integer -> (Integer, Integer, Integer)
-#if MIN_VERSION_integer_gmp(0,5,1)
-gcde_binary = gcde
-#else
-gcde_binary a' b'
-    | b' == 0   = (1,0,a')
-    | a' >= b'  = compute a' b'
-    | otherwise = (\(x,y,d) -> (y,x,d)) $ compute b' a'
-    where
-        getEvenMultiplier !g !x !y
-            | areEven [x,y] = getEvenMultiplier (g `shiftL` 1) (x `shiftR` 1) (y `shiftR` 1)
-            | otherwise     = (x,y,g)
-        halfLoop !x !y !u !i !j
-            | areEven [u,i,j] = halfLoop x y (u `shiftR` 1) (i `shiftR` 1) (j `shiftR` 1)
-            | even u          = halfLoop x y (u `shiftR` 1) ((i + y) `shiftR` 1) ((j - x) `shiftR` 1)
-            | otherwise       = (u, i, j)
-        compute a b =
-            let (x,y,g) = getEvenMultiplier 1 a b in
-            loop g x y x y 1 0 0 1
-
-        loop g _ _ 0  !v _  _  !c !d = (c, d, g * v)
-        loop g x y !u !v !a !b !c !d =
-            let (u2,a2,b2) = halfLoop x y u a b
-                (v2,c2,d2) = halfLoop x y v c d
-             in if u2 >= v2
-                then loop g x y (u2 - v2) v2 (a2 - c2) (b2 - d2) c2 d2
-                else loop g x y u2 (v2 - u2) a2 b2 (c2 - a2) (d2 - b2)
-#endif
 
 -- | check if a list of integer are all even
 areEven :: [Integer] -> Bool