Renommage des variables intermédiaires du tweakey schedule

x_{M^2,i}  me semble  moins lisible  que  b_i, et  pas forcément  plus
facile à traduire en (M²·x)[i].

1 files changed, 45 insertions, 46 deletions

diff --git a/src/ref/multiplications.h b/src/ref/multiplications.h
index c0645b9..ba68ad0 100644
--- a/src/ref/multiplications.h
+++ b/src/ref/multiplications.h
@@ -41,54 +41,53 @@ static void _multiply_M(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
 
 static void _multiply_M2(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
 {
-    uint8_t x_M_5 = x[5]<<3 ^ x[4];
-    uint8_t x_M_4 = x[4]>>3 ^ x[3];
+    uint8_t a5 = x[5]<<3 ^ x[4];
+    uint8_t a4 = x[4]>>3 ^ x[3];
 
     y[7] = x[5];
-    y[6] = x_M_5;
-    y[5] = x_M_5<<3 ^ x_M_4;
-    y[4] = x_M_4>>3 ^ x[2];
-    y[3] = x[6]<<2  ^ x[1];
-    y[2] = x[5]<<2  ^ x[0];
+    y[6] = a5;
+    y[5] = a5<<3   ^ a4;
+    y[4] = a4>>3   ^ x[2];
+    y[3] = x[6]<<2 ^ x[1];
+    y[2] = x[5]<<2 ^ x[0];
     y[1] = x[7];
     y[0] = x[6];
 }
 
 static void _multiply_M3(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
 {
-    uint8_t x_M_5  = x[5]<<3  ^ x[4];
-    uint8_t x_M_4  = x[4]>>3  ^ x[3];
-    uint8_t x_M2_5 = x_M_5<<3 ^ x_M_4;
-    uint8_t x_M2_4 = x_M_4>>3 ^ x[2];
-
-    y[7] = x_M_5;
-    y[6] = x_M2_5;
-    y[5] = x_M2_5<<3 ^ x_M2_4;
-    y[4] = x_M2_4>>3 ^ x[6]<<2 ^ x[1];
-    y[3] = x[5]<<2   ^ x[0];
-    y[2] = x_M_5<<2  ^ x[7];
+    uint8_t a5 = x[5]<<3 ^ x[4];
+    uint8_t a4 = x[4]>>3 ^ x[3];
+    uint8_t b5 = a5<<3   ^ a4;
+    uint8_t b4 = a4>>3   ^ x[2];
+
+    y[7] = a5;
+    y[6] = b5;
+    y[5] = b5<<3   ^ b4;
+    y[4] = b4>>3   ^ x[6]<<2 ^ x[1];
+    y[3] = x[5]<<2 ^ x[0];
+    y[2] = a5<<2   ^ x[7];
     y[1] = x[6];
     y[0] = x[5];
 }
 
 static void _multiply_M4(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
 {
-    uint8_t a_5  = x[5]<<3  ^ x[4];
-    uint8_t a_4  = x[4]>>3  ^ x[3];
-    uint8_t b_5 = a_5<<3 ^ a_4;
-    uint8_t b_4 = a_4>>3 ^ x[2];
-
-    uint8_t c_4 = b_4>>3 ^ x[6]<<2 ^ x[1];
-    uint8_t c_5 = b_5<<3 ^ b_4;
-
-    y[7] = b_5;
-    y[6] = c_5;
-    y[5] = c_5<<3 ^ c_4;
-    y[4] = c_4>>3 ^ x[5]<<2 ^ x[0];
-    y[3] = a_5<<2 ^ x[7];
-    y[2] = b_5<<2 ^ x[6];
+    uint8_t a5 = x[5]<<3 ^ x[4];
+    uint8_t a4 = x[4]>>3 ^ x[3];
+    uint8_t b5 = a5<<3   ^ a4;
+    uint8_t b4 = a4>>3   ^ x[2];
+    uint8_t c4 = b4>>3   ^ x[6]<<2 ^ x[1];
+    uint8_t c5 = b5<<3   ^ b4;
+
+    y[7] = b5;
+    y[6] = c5;
+    y[5] = c5<<3 ^ c4;
+    y[4] = c4>>3 ^ x[5]<<2 ^ x[0];
+    y[3] = a5<<2 ^ x[7];
+    y[2] = b5<<2 ^ x[6];
     y[1] = x[5];
-    y[0] = a_5;
+    y[0] = a5;
 }
 
 static void _multiply_MR(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
@@ -105,13 +104,13 @@ static void _multiply_MR(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
 
 static void _multiply_MR2(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
 {
-    uint8_t x_MR_4 = x[5] ^ x[6]<<3;
+    uint8_t a4 = x[5] ^ x[6]<<3;
 
     y[0] = x[2];
     y[1] = x[3]    ^ x[4]>>3;
-    y[2] = x[4]    ^ x_MR_4>>3;
-    y[3] = x_MR_4;
-    y[4] = x[3]<<2 ^ x[6]      ^ x[7]<<3;
+    y[2] = x[4]    ^ a4>>3;
+    y[3] = a4;
+    y[4] = x[3]<<2 ^ x[6]    ^ x[7]<<3;
     y[5] = x[4]<<2 ^ x[7];
     y[6] = x[0];
     y[7] = x[1];
@@ -119,15 +118,15 @@ static void _multiply_MR2(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
 
 static void _multiply_MR3(const uint8_t x[LANE_BYTES], uint8_t y[LANE_BYTES])
 {
-    uint8_t x_MR_4  = x[5]    ^ x[6]<<3;
-    uint8_t x_MR2_4 = x[3]<<2 ^ x[6]    ^ x[7]<<3;
-
-    y[0] = x[3]      ^ x[4]>>3;
-    y[1] = x[4]      ^ x_MR_4>>3;
-    y[2] = x_MR_4    ^ x_MR2_4>>3;
-    y[3] = x_MR2_4;
-    y[4] = x[0]<<3   ^ x[4]<<2   ^ x[7];
-    y[5] = x_MR_4<<2 ^ x[0];
+    uint8_t a4 = x[5]    ^ x[6]<<3;
+    uint8_t b4 = x[3]<<2 ^ x[6]    ^ x[7]<<3;
+
+    y[0] = x[3]    ^ x[4]>>3;
+    y[1] = x[4]    ^ a4>>3;
+    y[2] = a4      ^ b4>>3;
+    y[3] = b4;
+    y[4] = x[0]<<3 ^ x[4]<<2 ^ x[7];
+    y[5] = a4<<2   ^ x[0];
     y[6] = x[1];
     y[7] = x[2];
 }