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+########################################################################
+# Implement fast SHA-256 with AVX1 instructions. (x86_64)
+#
+# Copyright (C) 2013 Intel Corporation.
+#
+# Authors:
+# James Guilford <james.guilford@intel.com>
+# Kirk Yap <kirk.s.yap@intel.com>
+# Tim Chen <tim.c.chen@linux.intel.com>
+#
+# This software is available to you under a choice of one of two
+# licenses. You may choose to be licensed under the terms of the GNU
+# General Public License (GPL) Version 2, available from the file
+# COPYING in the main directory of this source tree, or the
+# OpenIB.org BSD license below:
+#
+# 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.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+########################################################################
+#
+# This code is described in an Intel White-Paper:
+# "Fast SHA-256 Implementations on Intel Architecture Processors"
+#
+# To find it, surf to http://www.intel.com/p/en_US/embedded
+# and search for that title.
+#
+########################################################################
+# This code schedules 1 block at a time, with 4 lanes per block
+########################################################################
+
+#include <linux/linkage.h>
+
+## assume buffers not aligned
+#define VMOVDQ vmovdqu
+
+################################ Define Macros
+
+# addm [mem], reg
+# Add reg to mem using reg-mem add and store
+.macro addm p1 p2
+ add \p1, \p2
+ mov \p2, \p1
+.endm
+
+
+.macro MY_ROR p1 p2
+ shld $(32-(\p1)), \p2, \p2
+.endm
+
+################################
+
+# COPY_XMM_AND_BSWAP xmm, [mem], byte_flip_mask
+# Load xmm with mem and byte swap each dword
+.macro COPY_XMM_AND_BSWAP p1 p2 p3
+ VMOVDQ \p2, \p1
+ vpshufb \p3, \p1, \p1
+.endm
+
+################################
+
+X0 = %xmm4
+X1 = %xmm5
+X2 = %xmm6
+X3 = %xmm7
+
+XTMP0 = %xmm0
+XTMP1 = %xmm1
+XTMP2 = %xmm2
+XTMP3 = %xmm3
+XTMP4 = %xmm8
+XFER = %xmm9
+XTMP5 = %xmm11
+
+SHUF_00BA = %xmm10 # shuffle xBxA -> 00BA
+SHUF_DC00 = %xmm12 # shuffle xDxC -> DC00
+BYTE_FLIP_MASK = %xmm13
+
+NUM_BLKS = %rdx # 3rd arg
+INP = %rsi # 2nd arg
+CTX = %rdi # 1st arg
+
+SRND = %rsi # clobbers INP
+c = %ecx
+d = %r8d
+e = %edx
+TBL = %r12
+a = %eax
+b = %ebx
+
+f = %r9d
+g = %r10d
+h = %r11d
+
+y0 = %r13d
+y1 = %r14d
+y2 = %r15d
+
+
+_INP_END_SIZE = 8
+_INP_SIZE = 8
+_XFER_SIZE = 16
+_XMM_SAVE_SIZE = 0
+
+_INP_END = 0
+_INP = _INP_END + _INP_END_SIZE
+_XFER = _INP + _INP_SIZE
+_XMM_SAVE = _XFER + _XFER_SIZE
+STACK_SIZE = _XMM_SAVE + _XMM_SAVE_SIZE
+
+# rotate_Xs
+# Rotate values of symbols X0...X3
+.macro rotate_Xs
+X_ = X0
+X0 = X1
+X1 = X2
+X2 = X3
+X3 = X_
+.endm
+
+# ROTATE_ARGS
+# Rotate values of symbols a...h
+.macro ROTATE_ARGS
+TMP_ = h
+h = g
+g = f
+f = e
+e = d
+d = c
+c = b
+b = a
+a = TMP_
+.endm
+
+.macro FOUR_ROUNDS_AND_SCHED
+ ## compute s0 four at a time and s1 two at a time
+ ## compute W[-16] + W[-7] 4 at a time
+
+ mov e, y0 # y0 = e
+ MY_ROR (25-11), y0 # y0 = e >> (25-11)
+ mov a, y1 # y1 = a
+ vpalignr $4, X2, X3, XTMP0 # XTMP0 = W[-7]
+ MY_ROR (22-13), y1 # y1 = a >> (22-13)
+ xor e, y0 # y0 = e ^ (e >> (25-11))
+ mov f, y2 # y2 = f
+ MY_ROR (11-6), y0 # y0 = (e >> (11-6)) ^ (e >> (25-6))
+ xor a, y1 # y1 = a ^ (a >> (22-13)
+ xor g, y2 # y2 = f^g
+ vpaddd X0, XTMP0, XTMP0 # XTMP0 = W[-7] + W[-16]
+ xor e, y0 # y0 = e ^ (e >> (11-6)) ^ (e >> (25-6))
+ and e, y2 # y2 = (f^g)&e
+ MY_ROR (13-2), y1 # y1 = (a >> (13-2)) ^ (a >> (22-2))
+ ## compute s0
+ vpalignr $4, X0, X1, XTMP1 # XTMP1 = W[-15]
+ xor a, y1 # y1 = a ^ (a >> (13-2)) ^ (a >> (22-2))
+ MY_ROR 6, y0 # y0 = S1 = (e>>6) & (e>>11) ^ (e>>25)
+ xor g, y2 # y2 = CH = ((f^g)&e)^g
+ MY_ROR 2, y1 # y1 = S0 = (a>>2) ^ (a>>13) ^ (a>>22)
+ add y0, y2 # y2 = S1 + CH
+ add _XFER(%rsp), y2 # y2 = k + w + S1 + CH
+ mov a, y0 # y0 = a
+ add y2, h # h = h + S1 + CH + k + w
+ mov a, y2 # y2 = a
+ vpsrld $7, XTMP1, XTMP2
+ or c, y0 # y0 = a|c
+ add h, d # d = d + h + S1 + CH + k + w
+ and c, y2 # y2 = a&c
+ vpslld $(32-7), XTMP1, XTMP3
+ and b, y0 # y0 = (a|c)&b
+ add y1, h # h = h + S1 + CH + k + w + S0
+ vpor XTMP2, XTMP3, XTMP3 # XTMP1 = W[-15] MY_ROR 7
+ or y2, y0 # y0 = MAJ = (a|c)&b)|(a&c)
+ add y0, h # h = h + S1 + CH + k + w + S0 + MAJ
+ ROTATE_ARGS
+ mov e, y0 # y0 = e
+ mov a, y1 # y1 = a
+ MY_ROR (25-11), y0 # y0 = e >> (25-11)
+ xor e, y0 # y0 = e ^ (e >> (25-11))
+ mov f, y2 # y2 = f
+ MY_ROR (22-13), y1 # y1 = a >> (22-13)
+ vpsrld $18, XTMP1, XTMP2 #
+ xor a, y1 # y1 = a ^ (a >> (22-13)
+ MY_ROR (11-6), y0 # y0 = (e >> (11-6)) ^ (e >> (25-6))
+ xor g, y2 # y2 = f^g
+ vpsrld $3, XTMP1, XTMP4 # XTMP4 = W[-15] >> 3
+ MY_ROR (13-2), y1 # y1 = (a >> (13-2)) ^ (a >> (22-2))
+ xor e, y0 # y0 = e ^ (e >> (11-6)) ^ (e >> (25-6))
+ and e, y2 # y2 = (f^g)&e
+ MY_ROR 6, y0 # y0 = S1 = (e>>6) & (e>>11) ^ (e>>25)
+ vpslld $(32-18), XTMP1, XTMP1
+ xor a, y1 # y1 = a ^ (a >> (13-2)) ^ (a >> (22-2))
+ xor g, y2 # y2 = CH = ((f^g)&e)^g
+ vpxor XTMP1, XTMP3, XTMP3 #
+ add y0, y2 # y2 = S1 + CH
+ add (1*4 + _XFER)(%rsp), y2 # y2 = k + w + S1 + CH
+ MY_ROR 2, y1 # y1 = S0 = (a>>2) ^ (a>>13) ^ (a>>22)
+ vpxor XTMP2, XTMP3, XTMP3 # XTMP1 = W[-15] MY_ROR 7 ^ W[-15] MY_ROR
+ mov a, y0 # y0 = a
+ add y2, h # h = h + S1 + CH + k + w
+ mov a, y2 # y2 = a
+ vpxor XTMP4, XTMP3, XTMP1 # XTMP1 = s0
+ or c, y0 # y0 = a|c
+ add h, d # d = d + h + S1 + CH + k + w
+ and c, y2 # y2 = a&c
+ ## compute low s1
+ vpshufd $0b11111010, X3, XTMP2 # XTMP2 = W[-2] {BBAA}
+ and b, y0 # y0 = (a|c)&b
+ add y1, h # h = h + S1 + CH + k + w + S0
+ vpaddd XTMP1, XTMP0, XTMP0 # XTMP0 = W[-16] + W[-7] + s0
+ or y2, y0 # y0 = MAJ = (a|c)&b)|(a&c)
+ add y0, h # h = h + S1 + CH + k + w + S0 + MAJ
+ ROTATE_ARGS
+ mov e, y0 # y0 = e
+ mov a, y1 # y1 = a
+ MY_ROR (25-11), y0 # y0 = e >> (25-11)
+ xor e, y0 # y0 = e ^ (e >> (25-11))
+ MY_ROR (22-13), y1 # y1 = a >> (22-13)
+ mov f, y2 # y2 = f
+ xor a, y1 # y1 = a ^ (a >> (22-13)
+ MY_ROR (11-6), y0 # y0 = (e >> (11-6)) ^ (e >> (25-6))
+ vpsrld $10, XTMP2, XTMP4 # XTMP4 = W[-2] >> 10 {BBAA}
+ xor g, y2 # y2 = f^g
+ vpsrlq $19, XTMP2, XTMP3 # XTMP3 = W[-2] MY_ROR 19 {xBxA}
+ xor e, y0 # y0 = e ^ (e >> (11-6)) ^ (e >> (25-6))
+ and e, y2 # y2 = (f^g)&e
+ vpsrlq $17, XTMP2, XTMP2 # XTMP2 = W[-2] MY_ROR 17 {xBxA}
+ MY_ROR (13-2), y1 # y1 = (a >> (13-2)) ^ (a >> (22-2))
+ xor a, y1 # y1 = a ^ (a >> (13-2)) ^ (a >> (22-2))
+ xor g, y2 # y2 = CH = ((f^g)&e)^g
+ MY_ROR 6, y0 # y0 = S1 = (e>>6) & (e>>11) ^ (e>>25)
+ vpxor XTMP3, XTMP2, XTMP2 #
+ add y0, y2 # y2 = S1 + CH
+ MY_ROR 2, y1 # y1 = S0 = (a>>2) ^ (a>>13) ^ (a>>22)
+ add (2*4 + _XFER)(%rsp), y2 # y2 = k + w + S1 + CH
+ vpxor XTMP2, XTMP4, XTMP4 # XTMP4 = s1 {xBxA}
+ mov a, y0 # y0 = a
+ add y2, h # h = h + S1 + CH + k + w
+ mov a, y2 # y2 = a
+ vpshufb SHUF_00BA, XTMP4, XTMP4 # XTMP4 = s1 {00BA}
+ or c, y0 # y0 = a|c
+ add h, d # d = d + h + S1 + CH + k + w
+ and c, y2 # y2 = a&c
+ vpaddd XTMP4, XTMP0, XTMP0 # XTMP0 = {..., ..., W[1], W[0]}
+ and b, y0 # y0 = (a|c)&b
+ add y1, h # h = h + S1 + CH + k + w + S0
+ ## compute high s1
+ vpshufd $0b01010000, XTMP0, XTMP2 # XTMP2 = W[-2] {DDCC}
+ or y2, y0 # y0 = MAJ = (a|c)&b)|(a&c)
+ add y0, h # h = h + S1 + CH + k + w + S0 + MAJ
+ ROTATE_ARGS
+ mov e, y0 # y0 = e
+ MY_ROR (25-11), y0 # y0 = e >> (25-11)
+ mov a, y1 # y1 = a
+ MY_ROR (22-13), y1 # y1 = a >> (22-13)
+ xor e, y0 # y0 = e ^ (e >> (25-11))
+ mov f, y2 # y2 = f
+ MY_ROR (11-6), y0 # y0 = (e >> (11-6)) ^ (e >> (25-6))
+ vpsrld $10, XTMP2, XTMP5 # XTMP5 = W[-2] >> 10 {DDCC}
+ xor a, y1 # y1 = a ^ (a >> (22-13)
+ xor g, y2 # y2 = f^g
+ vpsrlq $19, XTMP2, XTMP3 # XTMP3 = W[-2] MY_ROR 19 {xDxC}
+ xor e, y0 # y0 = e ^ (e >> (11-6)) ^ (e >> (25-6))
+ and e, y2 # y2 = (f^g)&e
+ MY_ROR (13-2), y1 # y1 = (a >> (13-2)) ^ (a >> (22-2))
+ vpsrlq $17, XTMP2, XTMP2 # XTMP2 = W[-2] MY_ROR 17 {xDxC}
+ xor a, y1 # y1 = a ^ (a >> (13-2)) ^ (a >> (22-2))
+ MY_ROR 6, y0 # y0 = S1 = (e>>6) & (e>>11) ^ (e>>25)
+ xor g, y2 # y2 = CH = ((f^g)&e)^g
+ vpxor XTMP3, XTMP2, XTMP2
+ MY_ROR 2, y1 # y1 = S0 = (a>>2) ^ (a>>13) ^ (a>>22)
+ add y0, y2 # y2 = S1 + CH
+ add (3*4 + _XFER)(%rsp), y2 # y2 = k + w + S1 + CH
+ vpxor XTMP2, XTMP5, XTMP5 # XTMP5 = s1 {xDxC}
+ mov a, y0 # y0 = a
+ add y2, h # h = h + S1 + CH + k + w
+ mov a, y2 # y2 = a
+ vpshufb SHUF_DC00, XTMP5, XTMP5 # XTMP5 = s1 {DC00}
+ or c, y0 # y0 = a|c
+ add h, d # d = d + h + S1 + CH + k + w
+ and c, y2 # y2 = a&c
+ vpaddd XTMP0, XTMP5, X0 # X0 = {W[3], W[2], W[1], W[0]}
+ and b, y0 # y0 = (a|c)&b
+ add y1, h # h = h + S1 + CH + k + w + S0
+ or y2, y0 # y0 = MAJ = (a|c)&b)|(a&c)
+ add y0, h # h = h + S1 + CH + k + w + S0 + MAJ
+ ROTATE_ARGS
+ rotate_Xs
+.endm
+
+## input is [rsp + _XFER + %1 * 4]
+.macro DO_ROUND round
+ mov e, y0 # y0 = e
+ MY_ROR (25-11), y0 # y0 = e >> (25-11)
+ mov a, y1 # y1 = a
+ xor e, y0 # y0 = e ^ (e >> (25-11))
+ MY_ROR (22-13), y1 # y1 = a >> (22-13)
+ mov f, y2 # y2 = f
+ xor a, y1 # y1 = a ^ (a >> (22-13)
+ MY_ROR (11-6), y0 # y0 = (e >> (11-6)) ^ (e >> (25-6))
+ xor g, y2 # y2 = f^g
+ xor e, y0 # y0 = e ^ (e >> (11-6)) ^ (e >> (25-6))
+ MY_ROR (13-2), y1 # y1 = (a >> (13-2)) ^ (a >> (22-2))
+ and e, y2 # y2 = (f^g)&e
+ xor a, y1 # y1 = a ^ (a >> (13-2)) ^ (a >> (22-2))
+ MY_ROR 6, y0 # y0 = S1 = (e>>6) & (e>>11) ^ (e>>25)
+ xor g, y2 # y2 = CH = ((f^g)&e)^g
+ add y0, y2 # y2 = S1 + CH
+ MY_ROR 2, y1 # y1 = S0 = (a>>2) ^ (a>>13) ^ (a>>22)
+ offset = \round * 4 + _XFER #
+ add offset(%rsp), y2 # y2 = k + w + S1 + CH
+ mov a, y0 # y0 = a
+ add y2, h # h = h + S1 + CH + k + w
+ mov a, y2 # y2 = a
+ or c, y0 # y0 = a|c
+ add h, d # d = d + h + S1 + CH + k + w
+ and c, y2 # y2 = a&c
+ and b, y0 # y0 = (a|c)&b
+ add y1, h # h = h + S1 + CH + k + w + S0
+ or y2, y0 # y0 = MAJ = (a|c)&b)|(a&c)
+ add y0, h # h = h + S1 + CH + k + w + S0 + MAJ
+ ROTATE_ARGS
+.endm
+
+########################################################################
+## void sha256_transform_avx(state sha256_state *state, const u8 *data, int blocks)
+## arg 1 : pointer to state
+## arg 2 : pointer to input data
+## arg 3 : Num blocks
+########################################################################
+.text
+SYM_FUNC_START(sha256_transform_avx)
+.align 32
+ pushq %rbx
+ pushq %r12
+ pushq %r13
+ pushq %r14
+ pushq %r15
+ pushq %rbp
+ movq %rsp, %rbp
+
+ subq $STACK_SIZE, %rsp # allocate stack space
+ and $~15, %rsp # align stack pointer
+
+ shl $6, NUM_BLKS # convert to bytes
+ jz done_hash
+ add INP, NUM_BLKS # pointer to end of data
+ mov NUM_BLKS, _INP_END(%rsp)
+
+ ## load initial digest
+ mov 4*0(CTX), a
+ mov 4*1(CTX), b
+ mov 4*2(CTX), c
+ mov 4*3(CTX), d
+ mov 4*4(CTX), e
+ mov 4*5(CTX), f
+ mov 4*6(CTX), g
+ mov 4*7(CTX), h
+
+ vmovdqa PSHUFFLE_BYTE_FLIP_MASK(%rip), BYTE_FLIP_MASK
+ vmovdqa _SHUF_00BA(%rip), SHUF_00BA
+ vmovdqa _SHUF_DC00(%rip), SHUF_DC00
+loop0:
+ lea K256(%rip), TBL
+
+ ## byte swap first 16 dwords
+ COPY_XMM_AND_BSWAP X0, 0*16(INP), BYTE_FLIP_MASK
+ COPY_XMM_AND_BSWAP X1, 1*16(INP), BYTE_FLIP_MASK
+ COPY_XMM_AND_BSWAP X2, 2*16(INP), BYTE_FLIP_MASK
+ COPY_XMM_AND_BSWAP X3, 3*16(INP), BYTE_FLIP_MASK
+
+ mov INP, _INP(%rsp)
+
+ ## schedule 48 input dwords, by doing 3 rounds of 16 each
+ mov $3, SRND
+.align 16
+loop1:
+ vpaddd (TBL), X0, XFER
+ vmovdqa XFER, _XFER(%rsp)
+ FOUR_ROUNDS_AND_SCHED
+
+ vpaddd 1*16(TBL), X0, XFER
+ vmovdqa XFER, _XFER(%rsp)
+ FOUR_ROUNDS_AND_SCHED
+
+ vpaddd 2*16(TBL), X0, XFER
+ vmovdqa XFER, _XFER(%rsp)
+ FOUR_ROUNDS_AND_SCHED
+
+ vpaddd 3*16(TBL), X0, XFER
+ vmovdqa XFER, _XFER(%rsp)
+ add $4*16, TBL
+ FOUR_ROUNDS_AND_SCHED
+
+ sub $1, SRND
+ jne loop1
+
+ mov $2, SRND
+loop2:
+ vpaddd (TBL), X0, XFER
+ vmovdqa XFER, _XFER(%rsp)
+ DO_ROUND 0
+ DO_ROUND 1
+ DO_ROUND 2
+ DO_ROUND 3
+
+ vpaddd 1*16(TBL), X1, XFER
+ vmovdqa XFER, _XFER(%rsp)
+ add $2*16, TBL
+ DO_ROUND 0
+ DO_ROUND 1
+ DO_ROUND 2
+ DO_ROUND 3
+
+ vmovdqa X2, X0
+ vmovdqa X3, X1
+
+ sub $1, SRND
+ jne loop2
+
+ addm (4*0)(CTX),a
+ addm (4*1)(CTX),b
+ addm (4*2)(CTX),c
+ addm (4*3)(CTX),d
+ addm (4*4)(CTX),e
+ addm (4*5)(CTX),f
+ addm (4*6)(CTX),g
+ addm (4*7)(CTX),h
+
+ mov _INP(%rsp), INP
+ add $64, INP
+ cmp _INP_END(%rsp), INP
+ jne loop0
+
+done_hash:
+
+ mov %rbp, %rsp
+ popq %rbp
+ popq %r15
+ popq %r14
+ popq %r13
+ popq %r12
+ popq %rbx
+ RET
+SYM_FUNC_END(sha256_transform_avx)
+
+.section .rodata.cst256.K256, "aM", @progbits, 256
+.align 64
+K256:
+ .long 0x428a2f98,0x71374491,0xb5c0fbcf,0xe9b5dba5
+ .long 0x3956c25b,0x59f111f1,0x923f82a4,0xab1c5ed5
+ .long 0xd807aa98,0x12835b01,0x243185be,0x550c7dc3
+ .long 0x72be5d74,0x80deb1fe,0x9bdc06a7,0xc19bf174
+ .long 0xe49b69c1,0xefbe4786,0x0fc19dc6,0x240ca1cc
+ .long 0x2de92c6f,0x4a7484aa,0x5cb0a9dc,0x76f988da
+ .long 0x983e5152,0xa831c66d,0xb00327c8,0xbf597fc7
+ .long 0xc6e00bf3,0xd5a79147,0x06ca6351,0x14292967
+ .long 0x27b70a85,0x2e1b2138,0x4d2c6dfc,0x53380d13
+ .long 0x650a7354,0x766a0abb,0x81c2c92e,0x92722c85
+ .long 0xa2bfe8a1,0xa81a664b,0xc24b8b70,0xc76c51a3
+ .long 0xd192e819,0xd6990624,0xf40e3585,0x106aa070
+ .long 0x19a4c116,0x1e376c08,0x2748774c,0x34b0bcb5
+ .long 0x391c0cb3,0x4ed8aa4a,0x5b9cca4f,0x682e6ff3
+ .long 0x748f82ee,0x78a5636f,0x84c87814,0x8cc70208
+ .long 0x90befffa,0xa4506ceb,0xbef9a3f7,0xc67178f2
+
+.section .rodata.cst16.PSHUFFLE_BYTE_FLIP_MASK, "aM", @progbits, 16
+.align 16
+PSHUFFLE_BYTE_FLIP_MASK:
+ .octa 0x0c0d0e0f08090a0b0405060700010203
+
+.section .rodata.cst16._SHUF_00BA, "aM", @progbits, 16
+.align 16
+# shuffle xBxA -> 00BA
+_SHUF_00BA:
+ .octa 0xFFFFFFFFFFFFFFFF0b0a090803020100
+
+.section .rodata.cst16._SHUF_DC00, "aM", @progbits, 16
+.align 16
+# shuffle xDxC -> DC00
+_SHUF_DC00:
+ .octa 0x0b0a090803020100FFFFFFFFFFFFFFFF