.list
.equ __zero_reg__, 1
+
+.global rho_pi_idx_table
+rho_pi_idx_table:
+ .irp i, 0, 1, 2, 3, 4
+ .irp j, 0, 1, 2, 3, 4
+ .byte (((2 * \j + 3 * \i) % 5) * 5 + \i) * 8
+ .endr
+ .endr
+
+.align 2
/*
void keccak_theta (uint64_t *a, uint64_t *b){
// uint64_t b[5][5];
.global keccak_theta
keccak_theta:
+ push_range 2, 8
+ push r16
+ push_range 28, 29
+
movw r30, r24 ; Z = a
movw r26, r22 ; X = b
+ push_range 22, 25
+
ldi r19, 5
10:
ldi r20, 8
sbci XH, hi8(4 * 5 * 8 + 8)
rcall theta_2b
+; ret
+/*
+ rho & pi
+ for(i = 0; i < 5; ++i){
+ for(j = 0; j < 5; ++j){
+ b[(2 * i + 3 * j) % 5][j] =
+ rotate64left_code(a[j][i], pgm_read_byte(&(keccak_rotate_codes[i][j])));
+ }
+ }
+
+ -- or --
+
+ const uint8_t* rot_code = (const uint8_t*)keccak_rotate_codes;
+ const uint8_t* idx_idx = (const uint8_t*)rho_pi_idx_table;
+ uint64_t *a_tmp = (uint64_t*)a;
+ for(i = 0; i < 25; ++i){
+ *((uint64_t*)(((uint8_t*)b) + pgm_read_byte(idx_idx++))) =
+ rotate64left_code(*a_tmp++, pgm_read_byte(rot_code++));
+
+ }
+
+*/
+
+.equ B_REG_L, 6
+.equ B_REG_H, 7
+
+ ldi r18, lo8(keccak_rotate_codes)
+ ldi r19, hi8(keccak_rotate_codes)
+ movw r2, r18
+ ldi r18, lo8(rho_pi_idx_table)
+ ldi r19, hi8(rho_pi_idx_table)
+ movw r4, r18
+ ldi r16, 25
+ mov r8, r16
+
+ pop YH
+ pop YL
+ pop B_REG_H
+ pop B_REG_L
+
+10:
+ ld r18, Y+
+ ld r19, Y+
+ ld r20, Y+
+ ld r21, Y+
+ ld r22, Y+
+ ld r23, Y+
+ ld r24, Y+
+ ld r25, Y+
+ movw ZL, r2
+ lpm r16, Z+
+ movw r2, ZL
+ call rotate64left_code
+ movw ZL, r4
+ lpm r16, Z+
+ movw r4, ZL
+ movw XL, B_REG_L
+ add XL, r16
+ adc XH, __zero_reg__
+ st X+, r18
+ st X+, r19
+ st X+, r20
+ st X+, r21
+ st X+, r22
+ st X+, r23
+ st X+, r24
+ st X+, r25
+
+ dec r8
+ brne 10b
+
+ pop_range 28, 29
+ pop r16
+ pop_range 2, 8
ret