diff --git a/ChangeLog b/ChangeLog
index e2180172364fc8253704839dc1c4466990fded7c..354ef00ee90da53118e16b448050425367e6d60f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
2011-06-12 Niels M�ller <nisse@lysator.liu.se>
+ * serpent-encrypt.c (SBOX6): Renamed arguments. Eliminated
+ temporaries.
+ (SBOX7): Likewise.
+ (All SBOX-macros): Deleted type argument, and updated users.
+
* configure.ac: Display summary at the end oc configure..
(asm_path): Set only if enable_assember is yes.
diff --git a/serpent-encrypt.c b/serpent-encrypt.c
index 5b9dab02054e5fdc1a6cab9fbfab3b056c042c59..fd3a68bb9a58cf57eda7110dd42136be502bab77 100644
--- a/serpent-encrypt.c
+++ b/serpent-encrypt.c
@@ -72,7 +72,7 @@
/* S0: 3 8 15 1 10 6 5 11 14 13 4 2 7 0 9 12 */
/* Could easily let y0, y1 overlap with x0, x1, and possibly also x2 and y2 */
-#define SBOX0(type, x0, x1, x2, x3, y0, y1, y2, y3) \
+#define SBOX0(x0, x1, x2, x3, y0, y1, y2, y3) \
do { \
y3 = x1 ^ x2; \
y0 = x0 | x3; \
@@ -96,7 +96,7 @@
/* FIXME: Arrange for some overlap between inputs and outputs? */
/* S1: 15 12 2 7 9 0 5 10 1 11 14 8 6 13 3 4 */
-#define SBOX1(type, x0, x1, x2, x3, y0, y1, y2, y3) \
+#define SBOX1(x0, x1, x2, x3, y0, y1, y2, y3) \
do { \
y1 = x0 | x3; \
y2 = x2 ^ x3; \
@@ -120,7 +120,7 @@
/* FIXME: Arrange for some overlap between inputs and outputs? */
/* S2: 8 6 7 9 3 12 10 15 13 1 14 4 0 11 5 2 */
-#define SBOX2(type, x0, x1, x2, x3, y0, y1, y2, y3) \
+#define SBOX2(x0, x1, x2, x3, y0, y1, y2, y3) \
do { \
y2 = x0 | x2; \
y1 = x0 ^ x1; \
@@ -162,7 +162,7 @@
y0 = t14 ^ t15;
y1 = t05 ^ t04;
*/
-#define SBOX3(type, x0, x1, x2, x3, y0, y1, y2, y3) \
+#define SBOX3(x0, x1, x2, x3, y0, y1, y2, y3) \
do { \
y2 = x0 ^ x2; \
y0 = x0 | x3; \
@@ -207,7 +207,7 @@
y1 = t15 ^ t16;
y0 = ~ t14;
*/
-#define SBOX4(type, x0, x1, x2, x3, y0, y1, y2, y3) \
+#define SBOX4(x0, x1, x2, x3, y0, y1, y2, y3) \
do { \
y3 = x0 | x1; \
y2 = x1 | x2; \
@@ -250,7 +250,7 @@
y1 = t07 ^ t08;
y3 = t12 ^ t14;
*/
-#define SBOX5(type, x0, x1, x2, x3, y0, y1, y2, y3) \
+#define SBOX5(x0, x1, x2, x3, y0, y1, y2, y3) \
do { \
y0 = x1 | x3; \
y0 ^= x2; \
@@ -272,55 +272,98 @@
} while (0)
/* S6: 7 2 12 5 8 4 6 11 14 9 1 15 13 3 10 0 */
-#define SBOX6(type, a, b, c, d, w, x, y, z) \
- do { \
- type t02, t03, t04, t05, t07, t08, t09, t10; \
- type t11, t12, t13, t15, t17, t18, t01; \
- t01 = a & d ; \
- t02 = b ^ c ; \
- t03 = a ^ d ; \
- t04 = t01 ^ t02; \
- t05 = b | c ; \
- x = ~ t04; \
- t07 = t03 & t05; \
- t08 = b & x ; \
- t09 = a | c ; \
- t10 = t07 ^ t08; \
- t11 = b | d ; \
- t12 = c ^ t11; \
- t13 = t09 ^ t10; \
- y = ~ t13; \
- t15 = x & t03; \
- z = t12 ^ t07; \
- t17 = a ^ b ; \
- t18 = y ^ t15; \
- w = t17 ^ t18; \
+/* Original single-assignment form:
+ t01 = x0 & x3;
+ t02 = x1 ^ x2;
+ t03 = x0 ^ x3;
+ t04 = t01 ^ t02;
+ t05 = x1 | x2;
+ y1 = ~ t04;
+ t07 = t03 & t05;
+ t08 = x1 & y1;
+ t09 = x0 | x2;
+ t10 = t07 ^ t08;
+ t11 = x1 | x3;
+ t12 = x2 ^ t11;
+ t13 = t09 ^ t10;
+ y2 = ~ t13;
+ t15 = y1 & t03;
+ y3 = t12 ^ t07;
+ t17 = x0 ^ x1;
+ t18 = y2 ^ t15;
+ y0 = t17 ^ t18;
+*/
+#define SBOX6(x0, x1, x2, x3, y0, y1, y2, y3) \
+ do { \
+ y0 = x0 ^ x3; \
+ y1 = x0 & x3; \
+ y2 = x0 | x2; \
+ x3 |= x1; \
+ x3 ^= x2; \
+ x0 ^= x1; \
+ y3 = x1 | x2; \
+ x2 ^= x1; \
+ y3 &= y0; \
+ y1 ^= x2; \
+ y1 = ~y1; \
+ y0 &= y1; \
+ x1 &= y1; \
+ x1 ^= y3; \
+ y3 ^= x3; \
+ y2 ^= x1; \
+ y2 = ~y2; \
+ y0 ^= y2; \
+ y0 ^= x0; \
} while (0)
/* S7: 1 13 15 0 14 8 2 11 7 4 12 10 9 3 5 6 */
-#define SBOX7(type, a, b, c, d, w, x, y, z) \
- do { \
- type t02, t03, t04, t05, t06, t08, t09, t10; \
- type t11, t13, t14, t15, t16, t17, t01; \
- t01 = a & c ; \
- t02 = ~ d ; \
- t03 = a & t02; \
- t04 = b | t01; \
- t05 = a & b ; \
- t06 = c ^ t04; \
- z = t03 ^ t06; \
- t08 = c | z ; \
- t09 = d | t05; \
- t10 = a ^ t08; \
- t11 = t04 & z ; \
- x = t09 ^ t10; \
- t13 = b ^ x ; \
- t14 = t01 ^ x ; \
- t15 = c ^ t05; \
- t16 = t11 | t13; \
- t17 = t02 | t14; \
- w = t15 ^ t17; \
- y = a ^ t16; \
+/* Original single-assignment form:
+ t01 = x0 & x2;
+ t02 = ~ x3;
+ t03 = x0 & t02;
+ t04 = x1 | t01;
+ t05 = x0 & x1;
+ t06 = x2 ^ t04;
+ y3 = t03 ^ t06;
+ t08 = x2 | y3;
+ t09 = x3 | t05;
+ t10 = x0 ^ t08;
+ t11 = t04 & y3;
+ y1 = t09 ^ t10;
+ t13 = x1 ^ y1;
+ t14 = t01 ^ y1;
+ t15 = x2 ^ t05;
+ t16 = t11 | t13;
+ t17 = t02 | t14;
+ y0 = t15 ^ t17;
+ y2 = x0 ^ t16;
+*/
+/* It appears impossible to do this with only 8 registers. We
+ recompute t02, and t04 (if we have spare registers, hopefully the
+ compiler can recognize it them as common subexpressions). */
+#define SBOX7(x0, x1, x2, x3, y0, y1, y2, y3) \
+ do { \
+ y0 = x0 & x2; \
+ y3 = x1 | y0; /* t04 */ \
+ y3 ^= x2; \
+ y1 = ~x3; /* t02 */ \
+ y1 &= x0; \
+ y3 ^= y1; \
+ y1 = x2 | y3; \
+ y1 ^= x0; \
+ y2 = x0 & x1; \
+ x2 ^= y2; \
+ y2 |= x3; \
+ y1 ^= y2; \
+ y2 = x1 | y0; /* t04 */ \
+ y2 &= y3; \
+ x1 ^= y1; \
+ y2 |= x1; \
+ y2 ^= x0; \
+ y0 ^= y1; \
+ x3 = ~x3; /* t02 */ \
+ y0 |= x3; \
+ y0 ^= x2; \
} while (0)
/* In-place linear transformation. */
@@ -343,7 +386,7 @@
#define ROUND(which, subkey, x0,x1,x2,x3, y0,y1,y2,y3) \
do { \
KEYXOR(x0,x1,x2,x3, subkey); \
- SBOX##which(uint32_t, x0,x1,x2,x3, y0,y1,y2,y3); \
+ SBOX##which(x0,x1,x2,x3, y0,y1,y2,y3); \
LINEAR_TRANSFORMATION(y0,y1,y2,y3); \
} while (0)
@@ -366,7 +409,7 @@
#define ROUND64(which, subkey, x0,x1,x2,x3, y0,y1,y2,y3) \
do { \
KEYXOR64(x0,x1,x2,x3, subkey); \
- SBOX##which(uint64_t, x0,x1,x2,x3, y0,y1,y2,y3); \
+ SBOX##which(x0,x1,x2,x3, y0,y1,y2,y3); \
LINEAR_TRANSFORMATION64(y0,y1,y2,y3); \
} while (0)
@@ -408,7 +451,7 @@ serpent_encrypt (const struct serpent_ctx *ctx,
/* Special final round, using two subkeys. */
KEYXOR (y0,y1,y2,y3, ctx->keys[31]);
- SBOX7 (uint32_t, y0,y1,y2,y3, x0,x1,x2,x3);
+ SBOX7 (y0,y1,y2,y3, x0,x1,x2,x3);
KEYXOR (x0,x1,x2,x3, ctx->keys[32]);
LE_WRITE_UINT32 (dst, x0);
@@ -452,7 +495,7 @@ serpent_encrypt (const struct serpent_ctx *ctx,
/* Special final round, using two subkeys. */
KEYXOR64 (y0,y1,y2,y3, ctx->keys[31]);
- SBOX7 (uint64_t, y0,y1,y2,y3, x0,x1,x2,x3);
+ SBOX7 (y0,y1,y2,y3, x0,x1,x2,x3);
KEYXOR64 (x0,x1,x2,x3, ctx->keys[32]);
LE_WRITE_UINT32 (dst + 16, x0);