Whitespace and comment changes.

Rev: nettle/serpent-encrypt.c:1.7

serpent-encrypt.c

@@ -141,6 +141,27 @@
   } while (0)
 
 /* S3:  0 15 11  8 12  9  6  3 13  1  2  4 10  7  5 14 */
+/* Original single-assignment form:
+   
+     t01 = x0  ^ x2;
+     t02 = x0  | x3;
+     t03 = x0  & x3;
+     t04 = t01 & t02;
+     t05 = x1  | t03;
+     t06 = x0  & x1;
+     t07 = x3  ^ t04;
+     t08 = x2  | t06;
+     t09 = x1  ^ t07;
+     t10 = x3  & t05;
+     t11 = t02 ^ t10;
+     y3  = t08 ^ t09;
+     t13 = x3  | y3;
+     t14 = x0  | t07;
+     t15 = x1  & t13;
+     y2  = t08 ^ t11;
+     y0  = t14 ^ t15;
+     y1  = t05 ^ t04;
+*/
 #define SBOX3(type, x0, x1, x2, x3, y0, y1, y2, y3)	\
   do {							\
     y2  = x0 ^ x2;					\
@@ -163,7 +184,29 @@
     y0  = x0 ^ x1;					\
   } while (0)
 
+
 /* S4:  1 15  8  3 12  0 11  6  2  5  4 10  9 14  7 13 */
+/* Original single-assignment form:
+    t01 = x0  | x1;
+    t02 = x1  | x2;
+    t03 = x0  ^ t02;
+    t04 = x1  ^ x3;
+    t05 = x3  | t03;
+    t06 = x3  & t01;
+    y3  = t03 ^ t06;
+    t08 = y3  & t04;
+    t09 = t04 & t05;
+    t10 = x2  ^ t06;
+    t11 = x1  & x2;
+    t12 = t04 ^ t08;
+    t13 = t11 | t03;
+    t14 = t10 ^ t09;
+    t15 = x0  & t05;
+    t16 = t11 | t12;
+    y2  = t13 ^ t08;
+    y1  = t15 ^ t16;
+    y0  =     ~ t14;
+*/
 #define SBOX4(type, x0, x1, x2, x3, y0, y1, y2, y3) \
   do { \
     type t02, t03, t04, t05, t06, t08, t09; \