.nolist
#include "avr-asm-macros.S"
.list
+
+.equ __zero_reg__, 1
/*
void keccak_theta (uint64_t *a, uint64_t *b){
// uint64_t b[5][5];
}
*/
-.global keccak_theta
-keccak_theta:
- movw r30, r24
- movw r26, r22
+/*********************************************
+ * theta_2a
+ *********************************************
+ input:
+ r24:r25 = a ; uint64_t a[5][5]
+ X = b ; uint64_t *b
+ output:
+ a[0..4][0] ^= b
+ r20 = 0
+ r21 = XX
+ r22 = XX
+ r24:r25 += 8
+ X += 8
+ Z = r24:r25 + 7 + 4 * 40
+*/
+theta_2a:
+ ldi r20, 8
+10:
+ movw ZL, r24
+ ld r21, X+
+ .irp r, 0, 1, 2, 3, 4
+ ld r22, Z
+ eor r22, r21
+ st Z, r22
+ .if \r != 4
+ adiw ZL, 40
+ .endif
+ .endr
+ adiw r24, 1
+ dec r20
+ brne 10b
+ ret
-; .irp offset, 0, 1, 2, 3, 4
+/*********************************************
+ * theta_2b
+ *********************************************
+ input:
+ r24:r25 = a+1 ; uint64_t a[5][5]
+ X = b ; uint64_t *b
+ output:
+ a[0..4][0] ^= rol(b,1)
+ r19 = XX
+ r20 = 0
+ r21 = XX
+ r22 = XX
+ r24:r25 += 8
+ X += 8
+ Z = r24:r25 + 7 + 4 * 40
+*/
+theta_2b:
+ ldi r20, 7
+ ld r19, X+
+ lsl r19
+ rol __zero_reg__
+10:
+ movw ZL, r24
+ ld r21, X+
+ ror __zero_reg__
+ rol r21
+ rol __zero_reg__
+ .irp r, 0, 1, 2, 3, 4
+ ld r22, Z
+ eor r22, r21
+ st Z, r22
+ .if \r != 4
+ adiw ZL, 40
+ .endif
+ .endr
+ adiw r24, 1
+ dec r20
+ brne 10b
+ add r19, __zero_reg__
+ sbiw r24, 8
+ movw ZL, r24
+ .irp r, 0, 1, 2, 3, 4
+ ld r22, Z
+ eor r22, r19
+ st Z, r22
+ .if \r != 4
+ adiw ZL, 40
+ .endif
+ .endr
+ adiw r24, 9
+ clr __zero_reg__
+ ret
+
+.global keccak_theta
+keccak_theta:
+ movw r30, r24 ; Z = a
+ movw r26, r22 ; X = b
ldi r19, 5
10:
ldi r20, 8
20:
-
ld r22, Z
adiw ZL, 40
ld r21, Z
adiw ZL, 40
ld r21, Z
eor r22, r21
-
adiw r24, 1
movw r30, r24
-
st X+, r22
dec r20
brne 20b
adiw XL, 8 * 4
dec r19
brne 10b
-; .endr
+/*
+ for(i = 0; i < 5; ++i){
+ for(j = 0; j < 5; ++j){
+ a[j][i] ^= b[(4 + i) % 5][0];
+ }
+ }
+
+*/
+/* a[0..4][0]{0..7} ^= b[4][0]{0..7} */
+ sbiw XL, 5 * 8
+ sbiw r24, 40
+ rcall theta_2a
+/* a[0..4][1]{0..7} ^= b[0][0]{0..7} */
+ subi XL, lo8(4 * 5 * 8 + 8)
+ sbci XH, hi8(4 * 5 * 8 + 8)
+ rcall theta_2a
+/* a[0..4][2]{0..7} ^= b[1][0]{0..7} */
+ adiw XL, 4 * 8
+ rcall theta_2a
+/* a[0..4][3]{0..7} ^= b[2][0]{0..7} */
+ adiw XL, 4 * 8
+ rcall theta_2a
+/* a[0..4][4]{0..7} ^= b[3][0]{0..7} */
+ adiw XL, 4 * 8
+ rcall theta_2a
+/*
+ for(i = 0; i < 5; ++i){
+ for(j = 0; j < 5; ++j){
+ a[j][i] ^= rotate64_1bit_left(b[(i + 1) % 5][0]);
+ }
+ }
+*/
+/* a[0..4][0]{0..7} ^= rol(b[1][0]{0..7}) */
+ subi r24, lo8(5 * 8 - 1)
+ sbci r25, hi8(5 * 8 - 1)
+ subi XL, lo8(2 * 5 * 8 + 8)
+ sbci XH, hi8(2 * 5 * 8 + 8)
+ rcall theta_2b
+/* a[0..4][1]{0..7} ^= rol(b[2][0]{0..7}) */
+ adiw XL, 4 * 8
+ rcall theta_2b
+/* a[0..4][21]{0..7} ^= rol(b[3][0]{0..7}) */
+ adiw XL, 4 * 8
+ rcall theta_2b
+/* a[0..4][3]{0..7} ^= rol(b[4][0]{0..7}) */
+ adiw XL, 4 * 8
+ rcall theta_2b
+/* a[0..4][4]{0..7} ^= rol(b[0][0]{0..7}) */
+ subi XL, lo8(4 * 5 * 8 + 8)
+ sbci XH, hi8(4 * 5 * 8 + 8)
+ rcall theta_2b
+
ret