;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Copyright(c) 2011-2015 Intel Corporation All rights reserved.
;
; Redistribution and use in source and binary forms, with or without
; modification, are permitted provided that the following conditions
; are met:
; * Redistributions of source code must retain the above copyright
; notice, this list of conditions and the following disclaimer.
; * Redistributions in binary form must reproduce the above copyright
; notice, this list of conditions and the following disclaimer in
; the documentation and/or other materials provided with the
; distribution.
; * Neither the name of Intel Corporation nor the names of its
; contributors may be used to endorse or promote products derived
; from this software without specific prior written permission.
;
; THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
; "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
; LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
; A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
; OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
; SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
; LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
; DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
; THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
; (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
; OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Function API:
; UINT16 crc16_t10dif_01(
; UINT16 init_crc, //initial CRC value, 16 bits
; const unsigned char *buf, //buffer pointer to calculate CRC on
; UINT64 len //buffer length in bytes (64-bit data)
; );
;
; Authors:
; Erdinc Ozturk
; Vinodh Gopal
; James Guilford
;
; Reference paper titled "Fast CRC Computation for Generic Polynomials Using PCLMULQDQ Instruction"
; URL: http://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf
%include "reg_sizes.asm"
%define fetch_dist 1024
[bits 64]
default rel
section .text
%ifidn __OUTPUT_FORMAT__, win64
%xdefine arg1 rcx
%xdefine arg2 rdx
%xdefine arg3 r8
%xdefine arg1_low32 ecx
%else
%xdefine arg1 rdi
%xdefine arg2 rsi
%xdefine arg3 rdx
%xdefine arg1_low32 edi
%endif
%ifidn __OUTPUT_FORMAT__, win64
%define XMM_SAVE 16*2
%define VARIABLE_OFFSET 16*10+8
%else
%define VARIABLE_OFFSET 16*2+8
%endif
align 16
mk_global crc16_t10dif_01, function
crc16_t10dif_01:
endbranch
; adjust the 16-bit initial_crc value, scale it to 32 bits
shl arg1_low32, 16
; After this point, code flow is exactly same as a 32-bit CRC.
; The only difference is before returning eax, we will shift it right 16 bits, to scale back to 16 bits.
sub rsp, VARIABLE_OFFSET
%ifidn __OUTPUT_FORMAT__, win64
; push the xmm registers into the stack to maintain
movdqa [rsp+16*2],xmm6
movdqa [rsp+16*3],xmm7
movdqa [rsp+16*4],xmm8
movdqa [rsp+16*5],xmm9
movdqa [rsp+16*6],xmm10
movdqa [rsp+16*7],xmm11
movdqa [rsp+16*8],xmm12
movdqa [rsp+16*9],xmm13
%endif
; check if smaller than 256
cmp arg3, 256
; for sizes less than 256, we can't fold 128B at a time...
jl _less_than_256
; load the initial crc value
movd xmm10, arg1_low32 ; initial crc
; crc value does not need to be byte-reflected, but it needs to be moved to the high part of the register.
; because data will be byte-reflected and will align with initial crc at correct place.
pslldq xmm10, 12
movdqa xmm11, [SHUF_MASK]
; receive the initial 128B data, xor the initial crc value
movdqu xmm0, [arg2+16*0]
movdqu xmm1, [arg2+16*1]
movdqu xmm2, [arg2+16*2]
movdqu xmm3, [arg2+16*3]
movdqu xmm4, [arg2+16*4]
movdqu xmm5, [arg2+16*5]
movdqu xmm6, [arg2+16*6]
movdqu xmm7, [arg2+16*7]
pshufb xmm0, xmm11
; XOR the initial_crc value
pxor xmm0, xmm10
pshufb xmm1, xmm11
pshufb xmm2, xmm11
pshufb xmm3, xmm11
pshufb xmm4, xmm11
pshufb xmm5, xmm11
pshufb xmm6, xmm11
pshufb xmm7, xmm11
movdqa xmm10, [rk3] ;xmm10 has rk3 and rk4
;imm value of pclmulqdq instruction will determine which constant to use
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; we subtract 256 instead of 128 to save one instruction from the loop
sub arg3, 256
; at this section of the code, there is 128*x+y (0<=y<128) bytes of buffer. The _fold_128_B_loop
; loop will fold 128B at a time until we have 128+y Bytes of buffer
; fold 128B at a time. This section of the code folds 8 xmm registers in parallel
_fold_128_B_loop:
; update the buffer pointer
add arg2, 128 ; buf += 128;
prefetchnta [arg2+fetch_dist+0]
movdqu xmm9, [arg2+16*0]
movdqu xmm12, [arg2+16*1]
pshufb xmm9, xmm11
pshufb xmm12, xmm11
movdqa xmm8, xmm0
movdqa xmm13, xmm1
pclmulqdq xmm0, xmm10, 0x0
pclmulqdq xmm8, xmm10 , 0x11
pclmulqdq xmm1, xmm10, 0x0
pclmulqdq xmm13, xmm10 , 0x11
pxor xmm0, xmm9
xorps xmm0, xmm8
pxor xmm1, xmm12
xorps xmm1, xmm13
prefetchnta [arg2+fetch_dist+32]
movdqu xmm9, [arg2+16*2]
movdqu xmm12, [arg2+16*3]
pshufb xmm9, xmm11
pshufb xmm12, xmm11
movdqa xmm8, xmm2
movdqa xmm13, xmm3
pclmulqdq xmm2, xmm10, 0x0
pclmulqdq xmm8, xmm10 , 0x11
pclmulqdq xmm3, xmm10, 0x0
pclmulqdq xmm13, xmm10 , 0x11
pxor xmm2, xmm9
xorps xmm2, xmm8
pxor xmm3, xmm12
xorps xmm3, xmm13
prefetchnta [arg2+fetch_dist+64]
movdqu xmm9, [arg2+16*4]
movdqu xmm12, [arg2+16*5]
pshufb xmm9, xmm11
pshufb xmm12, xmm11
movdqa xmm8, xmm4
movdqa xmm13, xmm5
pclmulqdq xmm4, xmm10, 0x0
pclmulqdq xmm8, xmm10 , 0x11
pclmulqdq xmm5, xmm10, 0x0
pclmulqdq xmm13, xmm10 , 0x11
pxor xmm4, xmm9
xorps xmm4, xmm8
pxor xmm5, xmm12
xorps xmm5, xmm13
prefetchnta [arg2+fetch_dist+96]
movdqu xmm9, [arg2+16*6]
movdqu xmm12, [arg2+16*7]
pshufb xmm9, xmm11
pshufb xmm12, xmm11
movdqa xmm8, xmm6
movdqa xmm13, xmm7
pclmulqdq xmm6, xmm10, 0x0
pclmulqdq xmm8, xmm10 , 0x11
pclmulqdq xmm7, xmm10, 0x0
pclmulqdq xmm13, xmm10 , 0x11
pxor xmm6, xmm9
xorps xmm6, xmm8
pxor xmm7, xmm12
xorps xmm7, xmm13
sub arg3, 128
; check if there is another 128B in the buffer to be able to fold
jge _fold_128_B_loop
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
add arg2, 128
; at this point, the buffer pointer is pointing at the last y Bytes of the buffer
; fold the 8 xmm registers to 1 xmm register with different constants
movdqa xmm10, [rk9]
movdqa xmm8, xmm0
pclmulqdq xmm0, xmm10, 0x11
pclmulqdq xmm8, xmm10, 0x0
pxor xmm7, xmm8
xorps xmm7, xmm0
movdqa xmm10, [rk11]
movdqa xmm8, xmm1
pclmulqdq xmm1, xmm10, 0x11
pclmulqdq xmm8, xmm10, 0x0
pxor xmm7, xmm8
xorps xmm7, xmm1
movdqa xmm10, [rk13]
movdqa xmm8, xmm2
pclmulqdq xmm2, xmm10, 0x11
pclmulqdq xmm8, xmm10, 0x0
pxor xmm7, xmm8
pxor xmm7, xmm2
movdqa xmm10, [rk15]
movdqa xmm8, xmm3
pclmulqdq xmm3, xmm10, 0x11
pclmulqdq xmm8, xmm10, 0x0
pxor xmm7, xmm8
xorps xmm7, xmm3
movdqa xmm10, [rk17]
movdqa xmm8, xmm4
pclmulqdq xmm4, xmm10, 0x11
pclmulqdq xmm8, xmm10, 0x0
pxor xmm7, xmm8
pxor xmm7, xmm4
movdqa xmm10, [rk19]
movdqa xmm8, xmm5
pclmulqdq xmm5, xmm10, 0x11
pclmulqdq xmm8, xmm10, 0x0
pxor xmm7, xmm8
xorps xmm7, xmm5
movdqa xmm10, [rk1] ;xmm10 has rk1 and rk2
;imm value of pclmulqdq instruction will determine which constant to use
movdqa xmm8, xmm6
pclmulqdq xmm6, xmm10, 0x11
pclmulqdq xmm8, xmm10, 0x0
pxor xmm7, xmm8
pxor xmm7, xmm6
; instead of 128, we add 112 to the loop counter to save 1 instruction from the loop
; instead of a cmp instruction, we use the negative flag with the jl instruction
add arg3, 128-16
jl _final_reduction_for_128
; now we have 16+y bytes left to reduce. 16 Bytes is in register xmm7 and the rest is in memory
; we can fold 16 bytes at a time if y>=16
; continue folding 16B at a time
_16B_reduction_loop:
movdqa xmm8, xmm7
pclmulqdq xmm7, xmm10, 0x11
pclmulqdq xmm8, xmm10, 0x0
pxor xmm7, xmm8
movdqu xmm0, [arg2]
pshufb xmm0, xmm11
pxor xmm7, xmm0
add arg2, 16
sub arg3, 16
; instead of a cmp instruction, we utilize the flags with the jge instruction
; equivalent of: cmp arg3, 16-16
; check if there is any more 16B in the buffer to be able to fold
jge _16B_reduction_loop
;now we have 16+z bytes left to reduce, where 0<= z < 16.
;first, we reduce the data in the xmm7 register
_final_reduction_for_128:
; check if any more data to fold. If not, compute the CRC of the final 128 bits
add arg3, 16
je _128_done
; here we are getting data that is less than 16 bytes.
; since we know that there was data before the pointer, we can offset the input pointer before the actual point, to receive exactly 16 bytes.
; after that the registers need to be adjusted.
_get_last_two_xmms:
movdqa xmm2, xmm7
movdqu xmm1, [arg2 - 16 + arg3]
pshufb xmm1, xmm11
; get rid of the extra data that was loaded before
; load the shift constant
lea rax, [pshufb_shf_table + 16]
sub rax, arg3
movdqu xmm0, [rax]
; shift xmm2 to the left by arg3 bytes
pshufb xmm2, xmm0
; shift xmm7 to the right by 16-arg3 bytes
pxor xmm0, [mask1]
pshufb xmm7, xmm0
pblendvb xmm1, xmm2 ;xmm0 is implicit
; fold 16 Bytes
movdqa xmm2, xmm1
movdqa xmm8, xmm7
pclmulqdq xmm7, xmm10, 0x11
pclmulqdq xmm8, xmm10, 0x0
pxor xmm7, xmm8
pxor xmm7, xmm2
_128_done:
; compute crc of a 128-bit value
movdqa xmm10, [rk5] ; rk5 and rk6 in xmm10
movdqa xmm0, xmm7
;64b fold
pclmulqdq xmm7, xmm10, 0x1
pslldq xmm0, 8
pxor xmm7, xmm0
;32b fold
movdqa xmm0, xmm7
pand xmm0, [mask2]
psrldq xmm7, 12
pclmulqdq xmm7, xmm10, 0x10
pxor xmm7, xmm0
;barrett reduction
_barrett:
movdqa xmm10, [rk7] ; rk7 and rk8 in xmm10
movdqa xmm0, xmm7
pclmulqdq xmm7, xmm10, 0x01
pslldq xmm7, 4
pclmulqdq xmm7, xmm10, 0x11
pslldq xmm7, 4
pxor xmm7, xmm0
pextrd eax, xmm7,1
_cleanup:
; scale the result back to 16 bits
shr eax, 16
%ifidn __OUTPUT_FORMAT__, win64
movdqa xmm6, [rsp+16*2]
movdqa xmm7, [rsp+16*3]
movdqa xmm8, [rsp+16*4]
movdqa xmm9, [rsp+16*5]
movdqa xmm10, [rsp+16*6]
movdqa xmm11, [rsp+16*7]
movdqa xmm12, [rsp+16*8]
movdqa xmm13, [rsp+16*9]
%endif
add rsp, VARIABLE_OFFSET
ret
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
align 16
_less_than_256:
; check if there is enough buffer to be able to fold 16B at a time
cmp arg3, 32
jl _less_than_32
movdqa xmm11, [SHUF_MASK]
; if there is, load the constants
movdqa xmm10, [rk1] ; rk1 and rk2 in xmm10
movd xmm0, arg1_low32 ; get the initial crc value
pslldq xmm0, 12 ; align it to its correct place
movdqu xmm7, [arg2] ; load the plaintext
pshufb xmm7, xmm11 ; byte-reflect the plaintext
pxor xmm7, xmm0
; update the buffer pointer
add arg2, 16
; update the counter. subtract 32 instead of 16 to save one instruction from the loop
sub arg3, 32
jmp _16B_reduction_loop
align 16
_less_than_32:
; mov initial crc to the return value. this is necessary for zero-length buffers.
mov eax, arg1_low32
test arg3, arg3
je _cleanup
movdqa xmm11, [SHUF_MASK]
movd xmm0, arg1_low32 ; get the initial crc value
pslldq xmm0, 12 ; align it to its correct place
cmp arg3, 16
je _exact_16_left
jl _less_than_16_left
movdqu xmm7, [arg2] ; load the plaintext
pshufb xmm7, xmm11 ; byte-reflect the plaintext
pxor xmm7, xmm0 ; xor the initial crc value
add arg2, 16
sub arg3, 16
movdqa xmm10, [rk1] ; rk1 and rk2 in xmm10
jmp _get_last_two_xmms
align 16
_less_than_16_left:
; use stack space to load data less than 16 bytes, zero-out the 16B in memory first.
pxor xmm1, xmm1
mov r11, rsp
movdqa [r11], xmm1
cmp arg3, 4
jl _only_less_than_4
; backup the counter value
mov r9, arg3
cmp arg3, 8
jl _less_than_8_left
; load 8 Bytes
mov rax, [arg2]
mov [r11], rax
add r11, 8
sub arg3, 8
add arg2, 8
_less_than_8_left:
cmp arg3, 4
jl _less_than_4_left
; load 4 Bytes
mov eax, [arg2]
mov [r11], eax
add r11, 4
sub arg3, 4
add arg2, 4
_less_than_4_left:
cmp arg3, 2
jl _less_than_2_left
; load 2 Bytes
mov ax, [arg2]
mov [r11], ax
add r11, 2
sub arg3, 2
add arg2, 2
_less_than_2_left:
cmp arg3, 1
jl _zero_left
; load 1 Byte
mov al, [arg2]
mov [r11], al
_zero_left:
movdqa xmm7, [rsp]
pshufb xmm7, xmm11
pxor xmm7, xmm0 ; xor the initial crc value
lea rax, [pshufb_shf_table + 16]
sub rax, r9
movdqu xmm0, [rax]
pxor xmm0, [mask1]
pshufb xmm7, xmm0
jmp _128_done
align 16
_exact_16_left:
movdqu xmm7, [arg2]
pshufb xmm7, xmm11
pxor xmm7, xmm0 ; xor the initial crc value
jmp _128_done
_only_less_than_4:
cmp arg3, 3
jl _only_less_than_3
; load 3 Bytes
mov al, [arg2]
mov [r11], al
mov al, [arg2+1]
mov [r11+1], al
mov al, [arg2+2]
mov [r11+2], al
movdqa xmm7, [rsp]
pshufb xmm7, xmm11
pxor xmm7, xmm0 ; xor the initial crc value
psrldq xmm7, 5
jmp _barrett
_only_less_than_3:
cmp arg3, 2
jl _only_less_than_2
; load 2 Bytes
mov al, [arg2]
mov [r11], al
mov al, [arg2+1]
mov [r11+1], al
movdqa xmm7, [rsp]
pshufb xmm7, xmm11
pxor xmm7, xmm0 ; xor the initial crc value
psrldq xmm7, 6
jmp _barrett
_only_less_than_2:
; load 1 Byte
mov al, [arg2]
mov [r11], al
movdqa xmm7, [rsp]
pshufb xmm7, xmm11
pxor xmm7, xmm0 ; xor the initial crc value
psrldq xmm7, 7
jmp _barrett
section .data
; precomputed constants
; these constants are precomputed from the poly: 0x8bb70000 (0x8bb7 scaled to 32 bits)
align 16
; Q = 0x18BB70000
; rk1 = 2^(32*3) mod Q << 32
; rk2 = 2^(32*5) mod Q << 32
; rk3 = 2^(32*15) mod Q << 32
; rk4 = 2^(32*17) mod Q << 32
; rk5 = 2^(32*3) mod Q << 32
; rk6 = 2^(32*2) mod Q << 32
; rk7 = floor(2^64/Q)
; rk8 = Q
rk1:
DQ 0x2d56000000000000
rk2:
DQ 0x06df000000000000
rk3:
DQ 0x9d9d000000000000
rk4:
DQ 0x7cf5000000000000
rk5:
DQ 0x2d56000000000000
rk6:
DQ 0x1368000000000000
rk7:
DQ 0x00000001f65a57f8
rk8:
DQ 0x000000018bb70000
rk9:
DQ 0xceae000000000000
rk10:
DQ 0xbfd6000000000000
rk11:
DQ 0x1e16000000000000
rk12:
DQ 0x713c000000000000
rk13:
DQ 0xf7f9000000000000
rk14:
DQ 0x80a6000000000000
rk15:
DQ 0x044c000000000000
rk16:
DQ 0xe658000000000000
rk17:
DQ 0xad18000000000000
rk18:
DQ 0xa497000000000000
rk19:
DQ 0x6ee3000000000000
rk20:
DQ 0xe7b5000000000000
mask1:
dq 0x8080808080808080, 0x8080808080808080
mask2:
dq 0xFFFFFFFFFFFFFFFF, 0x00000000FFFFFFFF
SHUF_MASK:
dq 0x08090A0B0C0D0E0F, 0x0001020304050607
pshufb_shf_table:
; use these values for shift constants for the pshufb instruction
; different alignments result in values as shown:
; dq 0x8887868584838281, 0x008f8e8d8c8b8a89 ; shl 15 (16-1) / shr1
; dq 0x8988878685848382, 0x01008f8e8d8c8b8a ; shl 14 (16-3) / shr2
; dq 0x8a89888786858483, 0x0201008f8e8d8c8b ; shl 13 (16-4) / shr3
; dq 0x8b8a898887868584, 0x030201008f8e8d8c ; shl 12 (16-4) / shr4
; dq 0x8c8b8a8988878685, 0x04030201008f8e8d ; shl 11 (16-5) / shr5
; dq 0x8d8c8b8a89888786, 0x0504030201008f8e ; shl 10 (16-6) / shr6
; dq 0x8e8d8c8b8a898887, 0x060504030201008f ; shl 9 (16-7) / shr7
; dq 0x8f8e8d8c8b8a8988, 0x0706050403020100 ; shl 8 (16-8) / shr8
; dq 0x008f8e8d8c8b8a89, 0x0807060504030201 ; shl 7 (16-9) / shr9
; dq 0x01008f8e8d8c8b8a, 0x0908070605040302 ; shl 6 (16-10) / shr10
; dq 0x0201008f8e8d8c8b, 0x0a09080706050403 ; shl 5 (16-11) / shr11
; dq 0x030201008f8e8d8c, 0x0b0a090807060504 ; shl 4 (16-12) / shr12
; dq 0x04030201008f8e8d, 0x0c0b0a0908070605 ; shl 3 (16-13) / shr13
; dq 0x0504030201008f8e, 0x0d0c0b0a09080706 ; shl 2 (16-14) / shr14
; dq 0x060504030201008f, 0x0e0d0c0b0a090807 ; shl 1 (16-15) / shr15
dq 0x8786858483828100, 0x8f8e8d8c8b8a8988
dq 0x0706050403020100, 0x000e0d0c0b0a0908
;;; func core, ver, snum
slversion crc16_t10dif_01, 01, 06, 0010