RISC-V: crypto: add a vector-crypto-accelerated SHA256
From: Heiko Stuebner <heiko.stuebner@...> Date: Thu, 2 Feb 2023 18:21:58 +0100
Commit-Message
This adds an accelerated SHA256 algorithm using either the Zvknha or Zvknhb vector crypto extensions. The spec says that Zvknhb supports SHA-256 and SHA-512. Zvknha supports only SHA-256. so the relevant acclerating instructions are included in both. Signed-off-by: Heiko Stuebner <heiko.stuebner@...>
Patch-Comment
arch/riscv/crypto/Kconfig | 10 + arch/riscv/crypto/Makefile | 7 + arch/riscv/crypto/sha256-riscv64-glue.c | 103 +++++ arch/riscv/crypto/sha256-riscv64-zvknha.pl | 502 +++++++++++++++++++++ 4 files changed, 622 insertions(+) create mode 100644 arch/riscv/crypto/sha256-riscv64-glue.c create mode 100644 arch/riscv/crypto/sha256-riscv64-zvknha.pl
Statistics
- 622 lines added
- 0 lines removed
Changes
-------------------------- arch/riscv/crypto/Kconfig ---------------------------
index 84da19bdde8b..c4e7d7526f1a 100644
@@ -15,4 +15,14 @@ config CRYPTO_GHASH_RISCV64
- ZVKB vector crypto extension
- ZVKG vector crypto extension
+config CRYPTO_SHA256_RISCV64
+ tristate "Hash functions: SHA-256"
+ depends on 64BIT && RISCV_ISA_V
+ select CRYPTO_HASH
+ help
+ SHA-256 secure hash algorithm (FIPS 180)
+
+ Architecture: riscv64 using
+ - Zvknha or Zvknhb vector crypto extensions
+
endmenu
-------------------------- arch/riscv/crypto/Makefile --------------------------
index 1ee0ce7d3264..02b3b4c32672 100644
@@ -12,6 +12,9 @@ ifdef CONFIG_RISCV_ISA_V
ghash-riscv64-y += ghash-riscv64-zvkb.o ghash-riscv64-zvkg.o
endif
+obj-$(CONFIG_CRYPTO_SHA256_RISCV64) += sha256-riscv64.o
+sha256-riscv64-y := sha256-riscv64-glue.o sha256-riscv64-zvknhb.o
+
quiet_cmd_perlasm = PERLASM $@
cmd_perlasm = $(PERL) $(<) void $(@)
@@ -24,4 +27,8 @@ $(obj)/ghash-riscv64-zvkb.S: $(src)/ghash-riscv64-zvkb.pl
$(obj)/ghash-riscv64-zvkg.S: $(src)/ghash-riscv64-zvkg.pl
$(call cmd,perlasm)
+$(obj)/sha256-riscv64-zvknhb.S: $(src)/sha256-riscv64-zvknha.pl
+ $(call cmd,perlasm)
+
clean-files += ghash-riscv64-zbc.S ghash-riscv64-zvkb.S ghash-riscv64-zvkg.S
+clean-files += sha256-riscv64-zvknha.S
------------------- arch/riscv/crypto/sha256-riscv64-glue.c --------------------
new file mode 100644
index 000000000000..bde46907a823
@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Linux/riscv64 port of the OpenSSL SHA256 implementation for RISCV64
+ */
+
+#include <linux/types.h>
+#include <asm/simd.h>
+#include <asm/vector.h>
+#include <crypto/internal/hash.h>
+#include <crypto/internal/simd.h>
+#include <crypto/sha2.h>
+#include <crypto/sha256_base.h>
+
+asmlinkage void sha256_block_data_order_zvknha(u32 *digest, const void *data,
+ unsigned int num_blks);
+EXPORT_SYMBOL(sha256_block_data_order_zvknha);
+
+static void __sha256_block_data_order(struct sha256_state *sst, u8 const *src,
+ int blocks)
+{
+ sha256_block_data_order_zvknha(sst->state, src, blocks);
+}
+
+static int riscv64_sha256_update(struct shash_desc *desc, const u8 *data,
+ unsigned int len)
+{
+ if (crypto_simd_usable()) {
+ int ret;
+
+ kernel_rvv_begin();
+ ret = sha256_base_do_update(desc, data, len,
+ __sha256_block_data_order);
+ kernel_rvv_end();
+ return ret;
+ } else {
+ return crypto_sha256_update(desc, data, len);
+ }
+}
+
+static int riscv64_sha256_finup(struct shash_desc *desc, const u8 *data,
+ unsigned int len, u8 *out)
+{
+ if (!crypto_simd_usable())
+ return crypto_sha256_finup(desc, data, len, out);
+
+ kernel_rvv_begin();
+ if (len)
+ sha256_base_do_update(desc, data, len,
+ __sha256_block_data_order);
+
+ sha256_base_do_finalize(desc, __sha256_block_data_order);
+ kernel_rvv_end();
+
+ return sha256_base_finish(desc, out);
+}
+
+static int riscv64_sha256_final(struct shash_desc *desc, u8 *out)
+{
+ return riscv64_sha256_finup(desc, NULL, 0, out);
+}
+
+static struct shash_alg sha256_alg = {
+ .digestsize = SHA256_DIGEST_SIZE,
+ .init = sha256_base_init,
+ .update = riscv64_sha256_update,
+ .final = riscv64_sha256_final,
+ .finup = riscv64_sha256_finup,
+ .descsize = sizeof(struct sha256_state),
+ .base.cra_name = "sha256",
+ .base.cra_driver_name = "sha256-riscv64-zvknha",
+ .base.cra_priority = 150,
+ .base.cra_blocksize = SHA256_BLOCK_SIZE,
+ .base.cra_module = THIS_MODULE,
+};
+
+static int __init sha256_mod_init(void)
+{
+ /*
+ * From the spec:
+ * Zvknhb supports SHA-256 and SHA-512. Zvknha supports only SHA-256.
+ */
+ if (riscv_isa_extension_available(NULL, ZVKNHA) ||
+ riscv_isa_extension_available(NULL, ZVKNHB))
+ return crypto_register_shash(&sha256_alg);
+
+ return 0;
+}
+
+static void __exit sha256_mod_fini(void)
+{
+ if (riscv_isa_extension_available(NULL, ZVKNHA) ||
+ riscv_isa_extension_available(NULL, ZVKNHB))
+ crypto_unregister_shash(&sha256_alg);
+}
+
+module_init(sha256_mod_init);
+module_exit(sha256_mod_fini);
+
+MODULE_DESCRIPTION("SHA-256 secure hash for riscv64");
+MODULE_AUTHOR("Andy Polyakov <appro@openssl.org>");
+MODULE_AUTHOR("Heiko Stuebner <heiko.stuebner@vrull.eu>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_CRYPTO("sha256");
------------------ arch/riscv/crypto/sha256-riscv64-zvknha.pl ------------------
new file mode 100644
index 000000000000..c15978926287
@@ -0,0 +1,502 @@
+#! /usr/bin/env perl
+# Copyright 2023 The OpenSSL Project Authors. All Rights Reserved.
+#
+# Licensed under the Apache License 2.0 (the "License"). You may not use
+# this file except in compliance with the License. You can obtain a copy
+# in the file LICENSE in the source distribution or at
+# https://www.openssl.org/source/license.html
+
+# The generated code of this file depends on the following RISC-V extensions:
+# - RV64I
+# - RISC-V vector ('V')
+# - Vector Bit-manipulation used in Cryptography ('Zvkb')
+# - Vector SHA-2 Secure Hash ('Zvknha')
+
+use strict;
+use warnings;
+
+use FindBin qw($Bin);
+use lib "$Bin";
+use lib "$Bin/../../perlasm";
+use riscv;
+
+# $output is the last argument if it looks like a file (it has an extension)
+# $flavour is the first argument if it doesn't look like a file
+my $output = $#ARGV >= 0 && $ARGV[$#ARGV] =~ m|\.\w+$| ? pop : undef;
+my $flavour = $#ARGV >= 0 && $ARGV[0] !~ m|\.| ? shift : undef;
+
+$output and open STDOUT,">$output";
+
+my $code=<<___;
+.text
+___
+
+my ($V0, $V10, $V11, $V12, $V13, $V14, $V15, $V16, $V17) = ("v0", "v10", "v11", "v12", "v13", "v14","v15", "v16", "v17");
+my ($V26, $V27) = ("v26", "v27");
+
+my $K256 = "K256";
+
+# Function arguments
+my ($H, $INP, $KT, $LEN, $STRIDE) = ("a0", "a1", "a2", "a3", "t3");
+
+################################################################################
+# void sha256_block_data_order(void *c, const void *p, size_t len)
+$code .= <<___;
+.p2align 2
+.globl sha256_block_data_order_zvknha
+.type sha256_block_data_order_zvknha,\@function
+sha256_block_data_order_zvknha:
+
+ # $LEN is stored in a2
+ mv $LEN, a2
+
+ # Register use in this function:
+ #
+ # SCALARS:
+ # a0 (i.e., x10): initially the address of the first byte of `hash`,
+ # modified during the logic.
+ # a1: initially the address of the first byte of the message block,
+ # modified during the initial load.
+ # a2: initially the address of the first byte of the round constants
+ # 'Kt', incremented during the rounds.
+ #
+ # VECTORS
+ # v10 - v13 (512-bits / 4*128 bits / 4*4*32 bits), hold the message
+ # schedule words (Wt). They start with the message block
+ # content (W0 to W15), then further words in the message
+ # schedule generated via vsha2ms from previous Wt.
+ # Initially:
+ # v10 = W[ 3:0] = { W3, W2, W1, W0}
+ # v11 = W[ 7:4] = { W7, W6, W5, W4}
+ # v12 = W[ 11:8] = {W11, W10, W9, W8}
+ # v13 = W[15:12] = {W15, W14, W13, W12}
+ #
+ # v16 - v17 hold the working state variables (a, b, ..., h)
+ # v16 = {a[t],b[t],e[t],f[t]}
+ # v17 = {c[t],d[t],g[t],h[t]}
+ # Initially:
+ # v16 = {H5i-1, H4i-1, H1i-1 , H0i-1}
+ # v17 = {H7i-i, H6i-1, H3i-1 , H2i-1}
+ #
+ # v0 = masks for vrgather/vmerge. Single value during the 16 rounds.
+ #
+ # v14 = temporary, Wt+Kt
+ # v15 = temporary, Kt
+ #
+ # v18/v19 = temporaries, in the epilogue, to re-arrange
+ # and byte-swap v16/v17
+ #
+ # v26/v27 = hold the initial values of the hash, byte-swapped.
+ #
+ # v30/v31 = used to generate masks, vrgather indices.
+ #
+ # During most of the function the vector state is configured so that each
+ # vector is interpreted as containing four 32 bits (e32) elements (128 bits).
+
+ # Set vectors as 4 * 32 bits
+ #
+ # e32: vector of 32b/4B elements
+ # m1: LMUL=1
+ # ta: tail agnostic (don't care about those lanes)
+ # ma: mask agnostic (don't care about those lanes)
+ # x0 is not written, we known the number of vector elements, 4.
+ @{[vsetivli__x0_4_e32_m1_ta_ma]}
+
+ # Load H[0..8] to produce
+ # v26 = v16 = {a[t],b[t],e[t],f[t]}
+ # v27 = v17 = {c[t],d[t],g[t],h[t]}
+ #
+ # To minimize per-block work, H is provided as {f,e,b,a, h,g,d,c}
+ # with the bytes in little endian order, i.e., not in NIST endianness
+ # or order.
+ @{[vle32_v $V16, $H]}
+ @{[vmv_v_v $V26, $V16]}
+ addi $H, $H, 16
+ @{[vle32_v $V17, $H]}
+ @{[vmv_v_v $V27, $V17]}
+ addi $H, $H, -16
+
+ @{[vslideup_vi $V16, $V27, 2]}
+ @{[vslidedown_vi $V17, $V26, 2]}
+ @{[vslidedown_vi $V26, $V27, 2]}
+ @{[vslideup_vi $V17, $V26, 2]}
+
+ @{[vse32_v $V16, $H]}
+ addi $H, $H, 16
+ @{[vse32_v $V17, $H]}
+ addi $H, $H, -16
+ @{[vmv_v_v $V26, $V16]}
+
+ li $STRIDE, -4
+
+ addi $H, $H, 12
+ @{[vlse32_v $V16, $H, $STRIDE]}
+ @{[vmv_v_v $V26, $V16]}
+
+ addi $H, $H, 16
+ @{[vlse32_v $V17, $H, $STRIDE]}
+ @{[vmv_v_v $V27, $V17]}
+ addi $H, $H, -28
+
+
+ # Load the 512-bits of the message block in v10-v13 and perform
+ # an endian swap on each 4 bytes element.
+ #
+ # If Zvkb is not implemented, one can use vrgather with the right index
+ # sequence. It requires loading in separate registers since the destination
+ # of vrgather cannot overlap the source.
+ # # We generate the lane (byte) index sequence
+ # # v24 = [3 2 1 0 7 6 5 4 11 10 9 8 15 14 13 12]
+ # # <https://oeis.org/A004444> gives us "N ^ 3" as a nice formula to generate
+ # # this sequence. 'vid' gives us the N.
+ # #
+ # # We switch the vector type to SEW=8 temporarily.
+ # vsetivli x0, 16, e8, m1, ta, ma
+ # vid.v v24
+ # vxor.vi v24, v24, 0x3
+ # # Byteswap the bytes in each word of the text.
+ # vrgather.vv v10, v20, v24
+ # vrgather.vv v11, v21, v24
+ # vrgather.vv v12, v22, v24
+ # vrgather.vv v13, v23, v24
+ # # Switch back to SEW=32
+ # vsetivli x0, 4, e32, m1, ta, ma
+
+L_round_loop:
+ la $KT, $K256 # Load round constants K256
+
+ # First loop part
+ @{[vle32_v $V10, $INP]}
+ @{[vrev8_v $V10, $V10]}
+ add $INP, $INP, 16
+ @{[vle32_v $V11, $INP]}
+ @{[vrev8_v $V11, $V11]}
+ add $INP, $INP, 16
+ @{[vle32_v $V12, $INP]}
+ @{[vrev8_v $V12, $V12]}
+ add $INP, $INP, 16
+ @{[vle32_v $V13, $INP]}
+ @{[vrev8_v $V13, $V13]}
+ add $INP, $INP, 16
+
+ # Decrement length by 1
+ add $LEN, $LEN, -1
+
+ # Set v0 up for the vmerge that replaces the first word (idx==0)
+ @{[vid_v $V0]}
+ @{[vmseq_vi $V0, $V0, 0x0]} # v0.mask[i] = (i == 0 ? 1 : 0)
+
+ # Overview of the logic in each "quad round".
+ #
+ # The code below repeats 16 times the logic implementing four rounds
+ # of the SHA-256 core loop as documented by NIST. 16 "quad rounds"
+ # to implementing the 64 single rounds.
+ #
+ # # Load four word (u32) constants (K[t+3], K[t+2], K[t+1], K[t+0])
+ # # Output:
+ # # v15 = {K[t+3], K[t+2], K[t+1], K[t+0]}
+ # vl1re32.v v15, (a2)
+ #
+ # # Increment word contant address by stride (16 bytes, 4*4B, 128b)
+ # addi a2, a2, 16
+ #
+ # # Add constants to message schedule words:
+ # # Input
+ # # v15 = {K[t+3], K[t+2], K[t+1], K[t+0]}
+ # # v10 = {W[t+3], W[t+2], W[t+1], W[t+0]}; // Vt0 = W[3:0];
+ # # Output
+ # # v14 = {W[t+3]+K[t+3], W[t+2]+K[t+2], W[t+1]+K[t+1], W[t+0]+K[t+0]}
+ # vadd.vv v14, v15, v10
+ #
+ # # 2 rounds of working variables updates.
+ # # v17[t+4] <- v17[t], v16[t], v14[t]
+ # # Input:
+ # # v17 = {c[t],d[t],g[t],h[t]} " = v17[t] "
+ # # v16 = {a[t],b[t],e[t],f[t]}
+ # # v14 = {W[t+3]+K[t+3], W[t+2]+K[t+2], W[t+1]+K[t+1], W[t+0]+K[t+0]}
+ # # Output:
+ # # v17 = {f[t+2],e[t+2],b[t+2],a[t+2]} " = v16[t+2] "
+ # # = {h[t+4],g[t+4],d[t+4],c[t+4]} " = v17[t+4] "
+ # vsha2cl.vv v17, v16, v14
+ #
+ # # 2 rounds of working variables updates.
+ # # v16[t+4] <- v16[t], v16[t+2], v14[t]
+ # # Input
+ # # v16 = {a[t],b[t],e[t],f[t]} " = v16[t] "
+ # # = {h[t+2],g[t+2],d[t+2],c[t+2]} " = v17[t+2] "
+ # # v17 = {f[t+2],e[t+2],b[t+2],a[t+2]} " = v16[t+2] "
+ # # v14 = {W[t+3]+K[t+3], W[t+2]+K[t+2], W[t+1]+K[t+1], W[t+0]+K[t+0]}
+ # # Output:
+ # # v16 = {f[t+4],e[t+4],b[t+4],a[t+4]} " = v16[t+4] "
+ # vsha2ch.vv v16, v17, v14
+ #
+ # # Combine 2QW into 1QW
+ # #
+ # # To generate the next 4 words, "new_v10"/"v14" from v10-v13, vsha2ms needs
+ # # v10[0..3], v11[0], v12[1..3], v13[0, 2..3]
+ # # and it can only take 3 vectors as inputs. Hence we need to combine
+ # # v11[0] and v12[1..3] in a single vector.
+ # #
+ # # vmerge Vt4, Vt1, Vt2, V0
+ # # Input
+ # # V0 = mask // first word from v12, 1..3 words from v11
+ # # V12 = {Wt-8, Wt-7, Wt-6, Wt-5}
+ # # V11 = {Wt-12, Wt-11, Wt-10, Wt-9}
+ # # Output
+ # # Vt4 = {Wt-12, Wt-7, Wt-6, Wt-5}
+ # vmerge.vvm v14, v12, v11, v0
+ #
+ # # Generate next Four Message Schedule Words (hence allowing for 4 more rounds)
+ # # Input
+ # # V10 = {W[t+ 3], W[t+ 2], W[t+ 1], W[t+ 0]} W[ 3: 0]
+ # # V13 = {W[t+15], W[t+14], W[t+13], W[t+12]} W[15:12]
+ # # V14 = {W[t+11], W[t+10], W[t+ 9], W[t+ 4]} W[11: 9,4]
+ # # Output (next four message schedule words)
+ # # v10 = {W[t+19], W[t+18], W[t+17], W[t+16]} W[19:16]
+ # vsha2ms.vv v10, v14, v13
+ #
+ # BEFORE
+ # v10 - v13 hold the message schedule words (initially the block words)
+ # v10 = W[ 3: 0] "oldest"
+ # v11 = W[ 7: 4]
+ # v12 = W[11: 8]
+ # v13 = W[15:12] "newest"
+ #
+ # vt6 - vt7 hold the working state variables
+ # v16 = {a[t],b[t],e[t],f[t]} // initially {H5,H4,H1,H0}
+ # v17 = {c[t],d[t],g[t],h[t]} // initially {H7,H6,H3,H2}
+ #
+ # AFTER
+ # v10 - v13 hold the message schedule words (initially the block words)
+ # v11 = W[ 7: 4] "oldest"
+ # v12 = W[11: 8]
+ # v13 = W[15:12]
+ # v10 = W[19:16] "newest"
+ #
+ # v16 and v17 hold the working state variables
+ # v16 = {a[t+4],b[t+4],e[t+4],f[t+4]}
+ # v17 = {c[t+4],d[t+4],g[t+4],h[t+4]}
+ #
+ # The group of vectors v10,v11,v12,v13 is "rotated" by one in each quad-round,
+ # hence the uses of those vectors rotate in each round, and we get back to the
+ # initial configuration every 4 quad-rounds. We could avoid those changes at
+ # the cost of moving those vectors at the end of each quad-rounds.
+
+ #--------------------------------------------------------------------------------
+ # Quad-round 0 (+0, Wt from oldest to newest in v10->v11->v12->v13)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V10]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V12, $V11, $V0]}
+ @{[vsha2ms_vv $V10, $V14, $V13]} # Generate W[19:16]
+ #--------------------------------------------------------------------------------
+ # Quad-round 1 (+1, v11->v12->v13->v10)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V11]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V13, $V12, $V0]}
+ @{[vsha2ms_vv $V11, $V14, $V10]} # Generate W[23:20]
+ #--------------------------------------------------------------------------------
+ # Quad-round 2 (+2, v12->v13->v10->v11)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V12]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V10, $V13, $V0]}
+ @{[vsha2ms_vv $V12, $V14, $V11]} # Generate W[27:24]
+ #--------------------------------------------------------------------------------
+ # Quad-round 3 (+3, v13->v10->v11->v12)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V13]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V11, $V10, $V0]}
+ @{[vsha2ms_vv $V13, $V14, $V12]} # Generate W[31:28]
+
+ #--------------------------------------------------------------------------------
+ # Quad-round 4 (+0, v10->v11->v12->v13)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V10]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V12, $V11, $V0]}
+ @{[vsha2ms_vv $V10, $V14, $V13]} # Generate W[35:32]
+ #--------------------------------------------------------------------------------
+ # Quad-round 5 (+1, v11->v12->v13->v10)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V11]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V13, $V12, $V0]}
+ @{[vsha2ms_vv $V11, $V14, $V10]} # Generate W[39:36]
+ #--------------------------------------------------------------------------------
+ # Quad-round 6 (+2, v12->v13->v10->v11)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V12]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V10, $V13, $V0]}
+ @{[vsha2ms_vv $V12, $V14, $V11]} # Generate W[43:40]
+ #--------------------------------------------------------------------------------
+ # Quad-round 7 (+3, v13->v10->v11->v12)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V13]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V11, $V10, $V0]}
+ @{[vsha2ms_vv $V13, $V14, $V12]} # Generate W[47:44]
+
+ #--------------------------------------------------------------------------------
+ # Quad-round 8 (+0, v10->v11->v12->v13)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V10]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V12, $V11, $V0]}
+ @{[vsha2ms_vv $V10, $V14, $V13]} # Generate W[51:48]
+ #--------------------------------------------------------------------------------
+ # Quad-round 9 (+1, v11->v12->v13->v10)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V11]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V13, $V12, $V0]}
+ @{[vsha2ms_vv $V11, $V14, $V10]} # Generate W[55:52]
+ #--------------------------------------------------------------------------------
+ # Quad-round 10 (+2, v12->v13->v10->v11)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V12]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V10, $V13, $V0]}
+ @{[vsha2ms_vv $V12, $V14, $V11]} # Generate W[59:56]
+ #--------------------------------------------------------------------------------
+ # Quad-round 11 (+3, v13->v10->v11->v12)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V13]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ @{[vmerge_vvm $V14, $V11, $V10, $V0]}
+ @{[vsha2ms_vv $V13, $V14, $V12]} # Generate W[63:60]
+
+ #--------------------------------------------------------------------------------
+ # Quad-round 12 (+0, v10->v11->v12->v13)
+ # Note that we stop generating new message schedule words (Wt, v10-13)
+ # as we already generated all the words we end up consuming (i.e., W[63:60]).
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V10]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ #--------------------------------------------------------------------------------
+ # Quad-round 13 (+1, v11->v12->v13->v10)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V11]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ #--------------------------------------------------------------------------------
+ # Quad-round 14 (+2, v12->v13->v10->v11)
+ @{[vl1re32_v $V15, $KT]}
+ addi $KT, $KT, 16
+ @{[vadd_vv $V14, $V15, $V12]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+ #--------------------------------------------------------------------------------
+ # Quad-round 15 (+3, v13->v10->v11->v12)
+ @{[vl1re32_v $V15, $KT]}
+ # No kt increment needed.
+ @{[vadd_vv $V14, $V15, $V13]}
+ @{[vsha2cl_vv $V17, $V16, $V14]}
+ @{[vslidedown_vi $V14, $V14, 2]}
+ @{[vsha2cl_vv $V16, $V17, $V14]}
+
+ # H' = H+{a',b',c',...,h'}
+ @{[vadd_vv $V16, $V26, $V16]}
+ @{[vadd_vv $V17, $V27, $V17]}
+ @{[vmv_v_v $V26, $V16]}
+ @{[vmv_v_v $V27, $V17]}
+ bnez $LEN, L_round_loop
+
+L_end:
+ @{[vmv_v_v $V26, $V16]}
+ @{[vmv_v_v $V27, $V17]}
+
+ addi $H, $H, 12
+ @{[vsse32_v $V16, $H, $STRIDE]}
+ @{[vmv_v_v $V26, $V16]}
+
+ addi $H, $H, 16
+ @{[vsse32_v $V17, $H, $STRIDE]}
+ @{[vmv_v_v $V27, $V17]}
+ addi $H, $H, -28
+
+ @{[vle32_v $V16, $H]}
+ @{[vmv_v_v $V26, $V16]}
+ addi $H, $H, 16
+ @{[vle32_v $V17, $H]}
+ @{[vmv_v_v $V27, $V17]}
+ addi $H, $H, -16
+
+ @{[vslideup_vi $V16, $V27, 2]}
+ @{[vslidedown_vi $V17, $V26, 2]}
+ @{[vslidedown_vi $V26, $V27, 2]}
+ @{[vslideup_vi $V17, $V26, 2]}
+
+ @{[vse32_v $V16, $H]}
+ addi $H, $H, 16
+ @{[vse32_v $V17, $H]}
+ ret
+
+.p2align 2
+.type $K256,\@object
+$K256:
+ .word 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5
+ .word 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5
+ .word 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3
+ .word 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174
+ .word 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc
+ .word 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da
+ .word 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7
+ .word 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967
+ .word 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13
+ .word 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85
+ .word 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3
+ .word 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070
+ .word 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5
+ .word 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3
+ .word 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208
+ .word 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
+___
+
+print $code;
+close STDOUT or die "error closing STDOUT: $!";