Réécriture de M³ en Python

1 files changed, 15 insertions, 52 deletions

diff --git a/src/add_python/lilliput/multiplications.py b/src/add_python/lilliput/multiplications.py
index 3b50987..c5abdfc 100644
--- a/src/add_python/lilliput/multiplications.py
+++ b/src/add_python/lilliput/multiplications.py
@@ -38,6 +38,9 @@ def _0(xi):
 def _M1(xi):
     return (xi<<3 ^ xi>>3) & 0xff
 
+def _M2(xi):
+    return (xi<<6 ^ (xi&0b11111000) ^ xi>>6) & 0xff
+
 
 M = (
     ( _0,    _Id,     _0,     _0,  _0,  _0,  _0,  _0),
@@ -61,6 +64,17 @@ M2 = (
     ( _0,    _Id,     _0,     _0,     _0,  _0,  _0,  _0),
 )
 
+M3 = (
+    ( _0,     _0, _Sl(3),    _Id,     _0,     _0,  _0,  _0),
+    ( _0,     _0, _Sl(6),    _M1,    _Id,     _0,  _0,  _0),
+    ( _0,     _0,     _0,    _M2,    _M1,    _Id,  _0,  _0),
+    ( _0, _Sl(2),     _0,     _0, _Sr(6), _Sr(3), _Id,  _0),
+    ( _0,     _0, _Sl(2),     _0,     _0,     _0,  _0, _Id),
+    (_Id,     _0, _Sl(5), _Sl(2),     _0,     _0,  _0,  _0),
+    ( _0,    _Id,     _0,     _0,     _0,     _0,  _0,  _0),
+    ( _0,     _0,    _Id,     _0,     _0,     _0,  _0,  _0),
+)
+
 
 def _multiplication(m):
     def _multiply(x):
@@ -72,57 +86,6 @@ def _multiplication(m):
     return _multiply
 
 
-def _multiply_M3(lane):
-    multiplied_lane = [lane[(byte-3) % 8] for byte in range(0, 8)]
-
-    multiplied_lane[2] ^= ((lane[4] << 2) & 0xff) ^ ((lane[5] << 5) & 0xff)
-    multiplied_lane[3] ^= ((lane[5] << 2) & 0xff)
-    multiplied_lane[4] ^= ((lane[2] >> 3) & 0xff) ^ ((lane[3] >> 6) & 0xff) ^ ((lane[6] << 2) & 0xff)
-    multiplied_lane[6] ^= ((lane[5] << 6) & 0xff)
-    multiplied_lane[7] ^= ((lane[5] << 3) & 0xff)
-
-    # binary matrix M1
-    multi_mat_l3_m1 = 0
-    l3 = lane[3]
-    multi_mat_l3_m1 ^= ((l3 & 0x8) >> 3)
-    multi_mat_l3_m1 ^= ((l3 & 0x10) >> 3)
-    multi_mat_l3_m1 ^= ((l3 & 0x20) >> 3)
-    multi_mat_l3_m1 ^= ((l3 & 0x40) >> 3) ^ ((l3 & 0x1) << 3)
-    multi_mat_l3_m1 ^= ((l3 & 0x80) >> 3) ^ ((l3 & 0x2) << 3)
-    multi_mat_l3_m1 ^= ((l3 & 0x04) << 3)
-    multi_mat_l3_m1 ^= ((l3 & 0x08) << 3)
-    multi_mat_l3_m1 ^= ((l3 & 0x10) << 3)
-
-    # binary matrix M1
-    multi_mat_l4_m1 = 0
-    l4 = lane[4]
-    multi_mat_l4_m1 ^= ((l4 & 0x8) >> 3)
-    multi_mat_l4_m1 ^= ((l4 & 0x10) >> 3)
-    multi_mat_l4_m1 ^= ((l4 & 0x20) >> 3)
-    multi_mat_l4_m1 ^= ((l4 & 0x40) >> 3) ^ ((l4 & 0x1) << 3)
-    multi_mat_l4_m1 ^= ((l4 & 0x80) >> 3) ^ ((l4 & 0x2) << 3)
-    multi_mat_l4_m1 ^= ((l4 & 0x04) << 3)
-    multi_mat_l4_m1 ^= ((l4 & 0x08) << 3)
-    multi_mat_l4_m1 ^= ((l4 & 0x10) << 3)
-
-    # binary matrix M2
-    multi_mat_l4_m2 = 0
-    l4 = lane[4]
-    multi_mat_l4_m2 ^= ((l4 & 0x40) >> 6)
-    multi_mat_l4_m2 ^= ((l4 & 0x80) >> 6)
-    multi_mat_l4_m2 ^= (l4 & 0x08)
-    multi_mat_l4_m2 ^= (l4 & 0x10)
-    multi_mat_l4_m2 ^= (l4 & 0x20)
-    multi_mat_l4_m2 ^= (l4 & 0x40) ^ ((l4 & 0x1) << 6)
-    multi_mat_l4_m2 ^= (l4 & 0x80) ^ ((l4 & 0x2) << 6)
-
-
-    multiplied_lane[5] ^= multi_mat_l3_m1 ^ multi_mat_l4_m2
-    multiplied_lane[6] ^= multi_mat_l4_m1
-
-    return multiplied_lane
-
-
 def _multiply_MR(lane):
     multiplied_lane = [lane[(byte+1) % 8] for byte in range(0, 8)]
 
@@ -217,7 +180,7 @@ ALPHAS = (
     list,                       # Identity.
     _multiplication(M),
     _multiplication(M2),
-    _multiply_M3,
+    _multiplication(M3),
     _multiply_MR,
     _multiply_MR2,
     _multiply_MR3