2015-09-11 06:27:13 +08:00
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/*
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* Intel SHA Extensions optimized implementation of a SHA-256 update function
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*
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* This file is provided under a dual BSD/GPLv2 license. When using or
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* redistributing this file, you may do so under either license.
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*
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* GPL LICENSE SUMMARY
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*
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* Copyright(c) 2015 Intel Corporation.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of version 2 of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* Contact Information:
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* Sean Gulley <sean.m.gulley@intel.com>
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* Tim Chen <tim.c.chen@linux.intel.com>
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*
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* BSD LICENSE
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*
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* Copyright(c) 2015 Intel Corporation.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* * Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* * Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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* * Neither the name of Intel Corporation nor the names of its
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* contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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*/
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#include <linux/linkage.h>
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#define DIGEST_PTR %rdi /* 1st arg */
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#define DATA_PTR %rsi /* 2nd arg */
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#define NUM_BLKS %rdx /* 3rd arg */
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#define SHA256CONSTANTS %rax
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#define MSG %xmm0
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#define STATE0 %xmm1
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#define STATE1 %xmm2
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#define MSGTMP0 %xmm3
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#define MSGTMP1 %xmm4
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#define MSGTMP2 %xmm5
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#define MSGTMP3 %xmm6
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#define MSGTMP4 %xmm7
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#define SHUF_MASK %xmm8
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#define ABEF_SAVE %xmm9
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#define CDGH_SAVE %xmm10
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/*
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* Intel SHA Extensions optimized implementation of a SHA-256 update function
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*
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* The function takes a pointer to the current hash values, a pointer to the
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* input data, and a number of 64 byte blocks to process. Once all blocks have
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* been processed, the digest pointer is updated with the resulting hash value.
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* The function only processes complete blocks, there is no functionality to
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* store partial blocks. All message padding and hash value initialization must
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* be done outside the update function.
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*
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* The indented lines in the loop are instructions related to rounds processing.
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* The non-indented lines are instructions related to the message schedule.
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*
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* void sha256_ni_transform(uint32_t *digest, const void *data,
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uint32_t numBlocks);
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* digest : pointer to digest
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* data: pointer to input data
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* numBlocks: Number of blocks to process
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*/
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.text
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.align 32
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ENTRY(sha256_ni_transform)
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shl $6, NUM_BLKS /* convert to bytes */
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jz .Ldone_hash
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add DATA_PTR, NUM_BLKS /* pointer to end of data */
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/*
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* load initial hash values
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* Need to reorder these appropriately
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* DCBA, HGFE -> ABEF, CDGH
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*/
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movdqu 0*16(DIGEST_PTR), STATE0
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movdqu 1*16(DIGEST_PTR), STATE1
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pshufd $0xB1, STATE0, STATE0 /* CDAB */
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pshufd $0x1B, STATE1, STATE1 /* EFGH */
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movdqa STATE0, MSGTMP4
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palignr $8, STATE1, STATE0 /* ABEF */
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pblendw $0xF0, MSGTMP4, STATE1 /* CDGH */
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movdqa PSHUFFLE_BYTE_FLIP_MASK(%rip), SHUF_MASK
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lea K256(%rip), SHA256CONSTANTS
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.Lloop0:
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/* Save hash values for addition after rounds */
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movdqa STATE0, ABEF_SAVE
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movdqa STATE1, CDGH_SAVE
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/* Rounds 0-3 */
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movdqu 0*16(DATA_PTR), MSG
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pshufb SHUF_MASK, MSG
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movdqa MSG, MSGTMP0
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paddd 0*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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/* Rounds 4-7 */
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movdqu 1*16(DATA_PTR), MSG
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pshufb SHUF_MASK, MSG
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movdqa MSG, MSGTMP1
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paddd 1*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP1, MSGTMP0
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/* Rounds 8-11 */
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movdqu 2*16(DATA_PTR), MSG
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pshufb SHUF_MASK, MSG
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movdqa MSG, MSGTMP2
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paddd 2*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP2, MSGTMP1
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/* Rounds 12-15 */
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movdqu 3*16(DATA_PTR), MSG
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pshufb SHUF_MASK, MSG
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movdqa MSG, MSGTMP3
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paddd 3*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP3, MSGTMP4
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palignr $4, MSGTMP2, MSGTMP4
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paddd MSGTMP4, MSGTMP0
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sha256msg2 MSGTMP3, MSGTMP0
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP3, MSGTMP2
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/* Rounds 16-19 */
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movdqa MSGTMP0, MSG
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paddd 4*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP0, MSGTMP4
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palignr $4, MSGTMP3, MSGTMP4
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paddd MSGTMP4, MSGTMP1
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sha256msg2 MSGTMP0, MSGTMP1
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP0, MSGTMP3
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/* Rounds 20-23 */
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movdqa MSGTMP1, MSG
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paddd 5*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP1, MSGTMP4
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palignr $4, MSGTMP0, MSGTMP4
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paddd MSGTMP4, MSGTMP2
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sha256msg2 MSGTMP1, MSGTMP2
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP1, MSGTMP0
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/* Rounds 24-27 */
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movdqa MSGTMP2, MSG
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paddd 6*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP2, MSGTMP4
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palignr $4, MSGTMP1, MSGTMP4
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paddd MSGTMP4, MSGTMP3
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sha256msg2 MSGTMP2, MSGTMP3
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP2, MSGTMP1
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/* Rounds 28-31 */
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movdqa MSGTMP3, MSG
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paddd 7*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP3, MSGTMP4
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palignr $4, MSGTMP2, MSGTMP4
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paddd MSGTMP4, MSGTMP0
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sha256msg2 MSGTMP3, MSGTMP0
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP3, MSGTMP2
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/* Rounds 32-35 */
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movdqa MSGTMP0, MSG
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paddd 8*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP0, MSGTMP4
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palignr $4, MSGTMP3, MSGTMP4
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paddd MSGTMP4, MSGTMP1
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sha256msg2 MSGTMP0, MSGTMP1
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP0, MSGTMP3
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/* Rounds 36-39 */
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movdqa MSGTMP1, MSG
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paddd 9*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP1, MSGTMP4
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palignr $4, MSGTMP0, MSGTMP4
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paddd MSGTMP4, MSGTMP2
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sha256msg2 MSGTMP1, MSGTMP2
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP1, MSGTMP0
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/* Rounds 40-43 */
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movdqa MSGTMP2, MSG
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paddd 10*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP2, MSGTMP4
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palignr $4, MSGTMP1, MSGTMP4
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paddd MSGTMP4, MSGTMP3
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sha256msg2 MSGTMP2, MSGTMP3
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP2, MSGTMP1
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/* Rounds 44-47 */
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movdqa MSGTMP3, MSG
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paddd 11*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP3, MSGTMP4
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palignr $4, MSGTMP2, MSGTMP4
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paddd MSGTMP4, MSGTMP0
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sha256msg2 MSGTMP3, MSGTMP0
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP3, MSGTMP2
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/* Rounds 48-51 */
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movdqa MSGTMP0, MSG
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paddd 12*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP0, MSGTMP4
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palignr $4, MSGTMP3, MSGTMP4
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paddd MSGTMP4, MSGTMP1
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sha256msg2 MSGTMP0, MSGTMP1
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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sha256msg1 MSGTMP0, MSGTMP3
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/* Rounds 52-55 */
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movdqa MSGTMP1, MSG
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paddd 13*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP1, MSGTMP4
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palignr $4, MSGTMP0, MSGTMP4
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paddd MSGTMP4, MSGTMP2
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sha256msg2 MSGTMP1, MSGTMP2
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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/* Rounds 56-59 */
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movdqa MSGTMP2, MSG
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paddd 14*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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movdqa MSGTMP2, MSGTMP4
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palignr $4, MSGTMP1, MSGTMP4
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paddd MSGTMP4, MSGTMP3
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sha256msg2 MSGTMP2, MSGTMP3
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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/* Rounds 60-63 */
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movdqa MSGTMP3, MSG
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paddd 15*16(SHA256CONSTANTS), MSG
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sha256rnds2 STATE0, STATE1
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pshufd $0x0E, MSG, MSG
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sha256rnds2 STATE1, STATE0
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/* Add current hash values with previously saved */
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paddd ABEF_SAVE, STATE0
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paddd CDGH_SAVE, STATE1
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/* Increment data pointer and loop if more to process */
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add $64, DATA_PTR
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cmp NUM_BLKS, DATA_PTR
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jne .Lloop0
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/* Write hash values back in the correct order */
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pshufd $0x1B, STATE0, STATE0 /* FEBA */
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pshufd $0xB1, STATE1, STATE1 /* DCHG */
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movdqa STATE0, MSGTMP4
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pblendw $0xF0, STATE1, STATE0 /* DCBA */
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palignr $8, MSGTMP4, STATE1 /* HGFE */
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movdqu STATE0, 0*16(DIGEST_PTR)
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movdqu STATE1, 1*16(DIGEST_PTR)
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.Ldone_hash:
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ret
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ENDPROC(sha256_ni_transform)
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crypto: x86 - make constants readonly, allow linker to merge them
A lot of asm-optimized routines in arch/x86/crypto/ keep its
constants in .data. This is wrong, they should be on .rodata.
Mnay of these constants are the same in different modules.
For example, 128-bit shuffle mask 0x000102030405060708090A0B0C0D0E0F
exists in at least half a dozen places.
There is a way to let linker merge them and use just one copy.
The rules are as follows: mergeable objects of different sizes
should not share sections. You can't put them all in one .rodata
section, they will lose "mergeability".
GCC puts its mergeable constants in ".rodata.cstSIZE" sections,
or ".rodata.cstSIZE.<object_name>" if -fdata-sections is used.
This patch does the same:
.section .rodata.cst16.SHUF_MASK, "aM", @progbits, 16
It is important that all data in such section consists of
16-byte elements, not larger ones, and there are no implicit
use of one element from another.
When this is not the case, use non-mergeable section:
.section .rodata[.VAR_NAME], "a", @progbits
This reduces .data by ~15 kbytes:
text data bss dec hex filename
11097415 2705840 2630712 16433967 fac32f vmlinux-prev.o
11112095 2690672 2630712 16433479 fac147 vmlinux.o
Merged objects are visible in System.map:
ffffffff81a28810 r POLY
ffffffff81a28810 r POLY
ffffffff81a28820 r TWOONE
ffffffff81a28820 r TWOONE
ffffffff81a28830 r PSHUFFLE_BYTE_FLIP_MASK <- merged regardless of
ffffffff81a28830 r SHUF_MASK <------------- the name difference
ffffffff81a28830 r SHUF_MASK
ffffffff81a28830 r SHUF_MASK
..
ffffffff81a28d00 r K512 <- merged three identical 640-byte tables
ffffffff81a28d00 r K512
ffffffff81a28d00 r K512
Use of object names in section name suffixes is not strictly necessary,
but might help if someday link stage will use garbage collection
to eliminate unused sections (ld --gc-sections).
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: Josh Poimboeuf <jpoimboe@redhat.com>
CC: Xiaodong Liu <xiaodong.liu@intel.com>
CC: Megha Dey <megha.dey@intel.com>
CC: linux-crypto@vger.kernel.org
CC: x86@kernel.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-01-20 05:33:04 +08:00
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.section .rodata.cst256.K256, "aM", @progbits, 256
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2015-09-11 06:27:13 +08:00
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.align 64
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K256:
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.long 0x428a2f98,0x71374491,0xb5c0fbcf,0xe9b5dba5
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.long 0x3956c25b,0x59f111f1,0x923f82a4,0xab1c5ed5
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.long 0xd807aa98,0x12835b01,0x243185be,0x550c7dc3
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.long 0x72be5d74,0x80deb1fe,0x9bdc06a7,0xc19bf174
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.long 0xe49b69c1,0xefbe4786,0x0fc19dc6,0x240ca1cc
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.long 0x2de92c6f,0x4a7484aa,0x5cb0a9dc,0x76f988da
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.long 0x983e5152,0xa831c66d,0xb00327c8,0xbf597fc7
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.long 0xc6e00bf3,0xd5a79147,0x06ca6351,0x14292967
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.long 0x27b70a85,0x2e1b2138,0x4d2c6dfc,0x53380d13
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.long 0x650a7354,0x766a0abb,0x81c2c92e,0x92722c85
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.long 0xa2bfe8a1,0xa81a664b,0xc24b8b70,0xc76c51a3
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.long 0xd192e819,0xd6990624,0xf40e3585,0x106aa070
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.long 0x19a4c116,0x1e376c08,0x2748774c,0x34b0bcb5
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.long 0x391c0cb3,0x4ed8aa4a,0x5b9cca4f,0x682e6ff3
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.long 0x748f82ee,0x78a5636f,0x84c87814,0x8cc70208
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.long 0x90befffa,0xa4506ceb,0xbef9a3f7,0xc67178f2
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crypto: x86 - make constants readonly, allow linker to merge them
A lot of asm-optimized routines in arch/x86/crypto/ keep its
constants in .data. This is wrong, they should be on .rodata.
Mnay of these constants are the same in different modules.
For example, 128-bit shuffle mask 0x000102030405060708090A0B0C0D0E0F
exists in at least half a dozen places.
There is a way to let linker merge them and use just one copy.
The rules are as follows: mergeable objects of different sizes
should not share sections. You can't put them all in one .rodata
section, they will lose "mergeability".
GCC puts its mergeable constants in ".rodata.cstSIZE" sections,
or ".rodata.cstSIZE.<object_name>" if -fdata-sections is used.
This patch does the same:
.section .rodata.cst16.SHUF_MASK, "aM", @progbits, 16
It is important that all data in such section consists of
16-byte elements, not larger ones, and there are no implicit
use of one element from another.
When this is not the case, use non-mergeable section:
.section .rodata[.VAR_NAME], "a", @progbits
This reduces .data by ~15 kbytes:
text data bss dec hex filename
11097415 2705840 2630712 16433967 fac32f vmlinux-prev.o
11112095 2690672 2630712 16433479 fac147 vmlinux.o
Merged objects are visible in System.map:
ffffffff81a28810 r POLY
ffffffff81a28810 r POLY
ffffffff81a28820 r TWOONE
ffffffff81a28820 r TWOONE
ffffffff81a28830 r PSHUFFLE_BYTE_FLIP_MASK <- merged regardless of
ffffffff81a28830 r SHUF_MASK <------------- the name difference
ffffffff81a28830 r SHUF_MASK
ffffffff81a28830 r SHUF_MASK
..
ffffffff81a28d00 r K512 <- merged three identical 640-byte tables
ffffffff81a28d00 r K512
ffffffff81a28d00 r K512
Use of object names in section name suffixes is not strictly necessary,
but might help if someday link stage will use garbage collection
to eliminate unused sections (ld --gc-sections).
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: Josh Poimboeuf <jpoimboe@redhat.com>
CC: Xiaodong Liu <xiaodong.liu@intel.com>
CC: Megha Dey <megha.dey@intel.com>
CC: linux-crypto@vger.kernel.org
CC: x86@kernel.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-01-20 05:33:04 +08:00
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.section .rodata.cst16.PSHUFFLE_BYTE_FLIP_MASK, "aM", @progbits, 16
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.align 16
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2015-09-11 06:27:13 +08:00
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PSHUFFLE_BYTE_FLIP_MASK:
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.octa 0x0c0d0e0f08090a0b0405060700010203
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