mirror of
https://github.com/torvalds/linux.git
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94a855111e
been long in the making. It is a lighterweight software-only fix for Skylake-based cores where enabling IBRS is a big hammer and causes a significant performance impact. What it basically does is, it aligns all kernel functions to 16 bytes boundary and adds a 16-byte padding before the function, objtool collects all functions' locations and when the mitigation gets applied, it patches a call accounting thunk which is used to track the call depth of the stack at any time. When that call depth reaches a magical, microarchitecture-specific value for the Return Stack Buffer, the code stuffs that RSB and avoids its underflow which could otherwise lead to the Intel variant of Retbleed. This software-only solution brings a lot of the lost performance back, as benchmarks suggest: https://lore.kernel.org/all/20220915111039.092790446@infradead.org/ That page above also contains a lot more detailed explanation of the whole mechanism - Implement a new control flow integrity scheme called FineIBT which is based on the software kCFI implementation and uses hardware IBT support where present to annotate and track indirect branches using a hash to validate them - Other misc fixes and cleanups -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmOZp5EACgkQEsHwGGHe VUrZFxAAvi/+8L0IYSK4mKJvixGbTFjxN/Swo2JVOfs34LqGUT6JaBc+VUMwZxdb VMTFIZ3ttkKEodjhxGI7oGev6V8UfhI37SmO2lYKXpQVjXXnMlv/M+Vw3teE38CN gopi+xtGnT1IeWQ3tc/Tv18pleJ0mh5HKWiW+9KoqgXj0wgF9x4eRYDz1TDCDA/A iaBzs56j8m/FSykZHnrWZ/MvjKNPdGlfJASUCPeTM2dcrXQGJ93+X2hJctzDte0y Nuiw6Y0htfFBE7xoJn+sqm5Okr+McoUM18/CCprbgSKYk18iMYm3ZtAi6FUQZS1A ua4wQCf49loGp15PO61AS5d3OBf5D3q/WihQRbCaJvTVgPp9sWYnWwtcVUuhMllh ZQtBU9REcVJ/22bH09Q9CjBW0VpKpXHveqQdqRDViLJ6v/iI6EFGmD24SW/VxyRd 73k9MBGrL/dOf1SbEzdsnvcSB3LGzp0Om8o/KzJWOomrVKjBCJy16bwTEsCZEJmP i406m92GPXeaN1GhTko7vmF0GnkEdJs1GVCZPluCAxxbhHukyxHnrjlQjI4vC80n Ylc0B3Kvitw7LGJsPqu+/jfNHADC/zhx1qz/30wb5cFmFbN1aRdp3pm8JYUkn+l/ zri2Y6+O89gvE/9/xUhMohzHsWUO7xITiBavewKeTP9GSWybWUs= =cRy1 -----END PGP SIGNATURE----- Merge tag 'x86_core_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 core updates from Borislav Petkov: - Add the call depth tracking mitigation for Retbleed which has been long in the making. It is a lighterweight software-only fix for Skylake-based cores where enabling IBRS is a big hammer and causes a significant performance impact. What it basically does is, it aligns all kernel functions to 16 bytes boundary and adds a 16-byte padding before the function, objtool collects all functions' locations and when the mitigation gets applied, it patches a call accounting thunk which is used to track the call depth of the stack at any time. When that call depth reaches a magical, microarchitecture-specific value for the Return Stack Buffer, the code stuffs that RSB and avoids its underflow which could otherwise lead to the Intel variant of Retbleed. This software-only solution brings a lot of the lost performance back, as benchmarks suggest: https://lore.kernel.org/all/20220915111039.092790446@infradead.org/ That page above also contains a lot more detailed explanation of the whole mechanism - Implement a new control flow integrity scheme called FineIBT which is based on the software kCFI implementation and uses hardware IBT support where present to annotate and track indirect branches using a hash to validate them - Other misc fixes and cleanups * tag 'x86_core_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (80 commits) x86/paravirt: Use common macro for creating simple asm paravirt functions x86/paravirt: Remove clobber bitmask from .parainstructions x86/debug: Include percpu.h in debugreg.h to get DECLARE_PER_CPU() et al x86/cpufeatures: Move X86_FEATURE_CALL_DEPTH from bit 18 to bit 19 of word 11, to leave space for WIP X86_FEATURE_SGX_EDECCSSA bit x86/Kconfig: Enable kernel IBT by default x86,pm: Force out-of-line memcpy() objtool: Fix weak hole vs prefix symbol objtool: Optimize elf_dirty_reloc_sym() x86/cfi: Add boot time hash randomization x86/cfi: Boot time selection of CFI scheme x86/ibt: Implement FineIBT objtool: Add --cfi to generate the .cfi_sites section x86: Add prefix symbols for function padding objtool: Add option to generate prefix symbols objtool: Avoid O(bloody terrible) behaviour -- an ode to libelf objtool: Slice up elf_create_section_symbol() kallsyms: Revert "Take callthunks into account" x86: Unconfuse CONFIG_ and X86_FEATURE_ namespaces x86/retpoline: Fix crash printing warning x86/paravirt: Fix a !PARAVIRT build warning ...
356 lines
10 KiB
ArmAsm
356 lines
10 KiB
ArmAsm
/*
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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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#include <linux/cfi_types.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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SYM_TYPED_FUNC_START(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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SYM_FUNC_END(sha256_ni_transform)
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.section .rodata.cst256.K256, "aM", @progbits, 256
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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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.section .rodata.cst16.PSHUFFLE_BYTE_FLIP_MASK, "aM", @progbits, 16
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.align 16
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PSHUFFLE_BYTE_FLIP_MASK:
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|
.octa 0x0c0d0e0f08090a0b0405060700010203
|