optimized rotates for keccak

[avr-crypto-lib.git] / keccak / rotate64.S

diff --git a/keccak/rotate64.S b/keccak/rotate64.S
new file mode 100644 (file)
index 0000000..5ab3a0f
--- /dev/null
+++ b/keccak/rotate64.S
@@ -0,0 +1,168 @@
+/* rotate64.S */
+/*
+    This file is part of the AVR-Crypto-Lib.
+    Copyright (C) 2006-2010 Daniel Otte (daniel.otte@rub.de)
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+.global rotate64_1bit_left
+rotate64_1bit_left:
+       bst r25, 7
+       rol r18
+       rol r19
+       rol r20
+       rol r21
+       rol r22
+       rol r23
+       rol r24
+       rol r25
+       bld r18, 0
+       ret
+
+.global rotate64_1bit_right
+rotate64_1bit_right:
+       bst r18, 0
+       ror r25
+       ror r24
+       ror r23
+       ror r22
+       ror r21
+       ror r20
+       ror r19
+       ror r18
+       bld r25, 7
+       ret
+
+.global rotate64_nbit_autodir
+rotate64_nbit_autodir:
+       lsr r16
+       brcc rotate64_nbit_left
+.global rotate64_nbit_right
+rotate64_nbit_right:
+       ldi r30, pm_lo8(rotate64_1bit_right)
+       ldi r31, pm_hi8(rotate64_1bit_right)
+       rjmp icall_r16_times
+.global rotate64_nbit_left
+rotate64_nbit_left:
+       ldi r30, pm_lo8(rotate64_1bit_left)
+       ldi r31, pm_hi8(rotate64_1bit_left)
+icall_r16_times:
+1:     dec r16
+       brmi 2f
+       icall
+       rjmp 1b
+2:
+       pop r16
+    ret
+
+rotate64_1byte_left:
+       mov r0, r25
+       mov r25, r24
+       mov r24, r23
+       mov r23, r22
+       mov r22, r21
+       mov r21, r20
+       mov r20, r19
+       mov r19, r18
+       mov r18, r0
+       ret
+
+rotate64_2byte_left:
+       movw r0, r24
+       movw r24, r22
+       movw r22, r20
+       movw r20, r18
+       movw r18, r0
+       ret
+
+rotate64_3byte_left:
+       mov r0, r25
+       mov r25, r22
+       mov r22, r19
+       mov r19, r24
+       mov r24, r21
+       mov r21, r18
+       mov r18, r23
+       mov r23, r20
+       mov r20, r0
+       ret
+
+rotate64_4byte_left:
+       movw r0, r24
+       movw r24, r20
+       movw r20, r0
+       movw r0, r22
+       movw r22, r18
+       movw r18, r0
+       ret
+
+rotate64_5byte_left:
+       mov r0, r25
+       mov r25, r20
+       mov r20, r23
+       mov r23, r18
+       mov r18, r21
+       mov r21, r24
+       mov r24, r19
+       mov r19, r22
+       mov r22, r0
+       ret
+
+rotate64_6byte_left:
+       movw r0, r18
+       movw r18, r20
+       movw r20, r22
+       movw r22, r24
+       movw r24, r0
+       ret
+
+rotate64_7byte_left:
+       mov r0, r18
+       mov r18, r19
+       mov r19, r20
+       mov r20, r21
+       mov r21, r22
+       mov r22, r23
+       mov r23, r24
+       mov r24, r25
+       mov r25, r0
+       ret
+
+
+byte_rot_jmp_table:
+       ret
+       rjmp rotate64_1byte_left
+       rjmp rotate64_2byte_left
+       rjmp rotate64_3byte_left
+       rjmp rotate64_4byte_left
+       rjmp rotate64_5byte_left
+       rjmp rotate64_6byte_left
+       rjmp rotate64_7byte_left
+
+.global rotate64left_code
+rotate64left_code:
+       ldi r30, pm_lo8(byte_rot_jmp_table)
+       ldi r31, pm_hi8(byte_rot_jmp_table)
+       push r16
+       mov r0, r16
+       andi r16, 0x70
+       swap r16
+       add r30, r16
+       adc r31, r1
+       mov r16, r0
+       andi r16, 0x0f
+       icall
+       clr r1
+       rjmp rotate64_nbit_autodir