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-rw-r--r--src/liblzma/check/Makefile.inc15
-rw-r--r--src/liblzma/check/check.c5
-rw-r--r--src/liblzma/check/check.h5
-rw-r--r--src/liblzma/check/crc32_arm64.h122
-rw-r--r--src/liblzma/check/crc32_fast.c158
-rw-r--r--src/liblzma/check/crc32_small.c5
-rw-r--r--src/liblzma/check/crc32_table.c34
-rw-r--r--src/liblzma/check/crc32_table_be.h4
-rw-r--r--src/liblzma/check/crc32_table_le.h4
-rw-r--r--src/liblzma/check/crc32_tablegen.c23
-rw-r--r--src/liblzma/check/crc32_x86.S5
-rw-r--r--src/liblzma/check/crc64_fast.c446
-rw-r--r--src/liblzma/check/crc64_small.c5
-rw-r--r--src/liblzma/check/crc64_table.c16
-rw-r--r--src/liblzma/check/crc64_table_be.h4
-rw-r--r--src/liblzma/check/crc64_table_le.h4
-rw-r--r--src/liblzma/check/crc64_tablegen.c15
-rw-r--r--src/liblzma/check/crc64_x86.S5
-rw-r--r--src/liblzma/check/crc_common.h137
-rw-r--r--src/liblzma/check/crc_macros.h30
-rw-r--r--src/liblzma/check/crc_x86_clmul.h428
-rw-r--r--src/liblzma/check/sha256.c19
22 files changed, 954 insertions, 535 deletions
diff --git a/src/liblzma/check/Makefile.inc b/src/liblzma/check/Makefile.inc
index dc011a3..04cf1ff 100644
--- a/src/liblzma/check/Makefile.inc
+++ b/src/liblzma/check/Makefile.inc
@@ -1,9 +1,8 @@
-##
+## SPDX-License-Identifier: 0BSD
## Author: Lasse Collin
-##
-## This file has been put into the public domain.
-## You can do whatever you want with this file.
-##
+
+## Note: There is no check for COND_CHECK_CRC32 because
+## currently crc32 is always enabled.
EXTRA_DIST += \
check/crc32_tablegen.c \
@@ -12,9 +11,10 @@ EXTRA_DIST += \
liblzma_la_SOURCES += \
check/check.c \
check/check.h \
- check/crc_macros.h
+ check/crc_common.h \
+ check/crc_x86_clmul.h \
+ check/crc32_arm64.h
-if COND_CHECK_CRC32
if COND_SMALL
liblzma_la_SOURCES += check/crc32_small.c
else
@@ -28,7 +28,6 @@ else
liblzma_la_SOURCES += check/crc32_fast.c
endif
endif
-endif
if COND_CHECK_CRC64
if COND_SMALL
diff --git a/src/liblzma/check/check.c b/src/liblzma/check/check.c
index 428ddae..7734ace 100644
--- a/src/liblzma/check/check.c
+++ b/src/liblzma/check/check.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: 0BSD
+
///////////////////////////////////////////////////////////////////////////////
//
/// \file check.c
@@ -5,9 +7,6 @@
//
// Author: Lasse Collin
//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
-//
///////////////////////////////////////////////////////////////////////////////
#include "check.h"
diff --git a/src/liblzma/check/check.h b/src/liblzma/check/check.h
index 8ae95d5..f0eb117 100644
--- a/src/liblzma/check/check.h
+++ b/src/liblzma/check/check.h
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: 0BSD
+
///////////////////////////////////////////////////////////////////////////////
//
/// \file check.h
@@ -5,9 +7,6 @@
//
// Author: Lasse Collin
//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
-//
///////////////////////////////////////////////////////////////////////////////
#ifndef LZMA_CHECK_H
diff --git a/src/liblzma/check/crc32_arm64.h b/src/liblzma/check/crc32_arm64.h
new file mode 100644
index 0000000..39c1c63
--- /dev/null
+++ b/src/liblzma/check/crc32_arm64.h
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: 0BSD
+
+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file crc32_arm64.h
+/// \brief CRC32 calculation with ARM64 optimization
+//
+// Authors: Chenxi Mao
+// Jia Tan
+// Hans Jansen
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#ifndef LZMA_CRC32_ARM64_H
+#define LZMA_CRC32_ARM64_H
+
+// MSVC always has the CRC intrinsics available when building for ARM64
+// there is no need to include any header files.
+#ifndef _MSC_VER
+# include <arm_acle.h>
+#endif
+
+// If both versions are going to be built, we need runtime detection
+// to check if the instructions are supported.
+#if defined(CRC32_GENERIC) && defined(CRC32_ARCH_OPTIMIZED)
+# if defined(HAVE_GETAUXVAL) || defined(HAVE_ELF_AUX_INFO)
+# include <sys/auxv.h>
+# elif defined(_WIN32)
+# include <processthreadsapi.h>
+# elif defined(__APPLE__) && defined(HAVE_SYSCTLBYNAME)
+# include <sys/sysctl.h>
+# endif
+#endif
+
+// Some EDG-based compilers support ARM64 and define __GNUC__
+// (such as Nvidia's nvcc), but do not support function attributes.
+//
+// NOTE: Build systems check for this too, keep them in sync with this.
+#if (defined(__GNUC__) || defined(__clang__)) && !defined(__EDG__)
+# define crc_attr_target __attribute__((__target__("+crc")))
+#else
+# define crc_attr_target
+#endif
+
+
+crc_attr_target
+static uint32_t
+crc32_arch_optimized(const uint8_t *buf, size_t size, uint32_t crc)
+{
+ crc = ~crc;
+
+ // Align the input buffer because this was shown to be
+ // significantly faster than unaligned accesses.
+ const size_t align_amount = my_min(size, (0U - (uintptr_t)buf) & 7);
+
+ for (const uint8_t *limit = buf + align_amount; buf < limit; ++buf)
+ crc = __crc32b(crc, *buf);
+
+ size -= align_amount;
+
+ // Process 8 bytes at a time. The end point is determined by
+ // ignoring the least significant three bits of size to ensure
+ // we do not process past the bounds of the buffer. This guarantees
+ // that limit is a multiple of 8 and is strictly less than size.
+ for (const uint8_t *limit = buf + (size & ~(size_t)7);
+ buf < limit; buf += 8)
+ crc = __crc32d(crc, aligned_read64le(buf));
+
+ // Process the remaining bytes that are not 8 byte aligned.
+ for (const uint8_t *limit = buf + (size & 7); buf < limit; ++buf)
+ crc = __crc32b(crc, *buf);
+
+ return ~crc;
+}
+
+
+#if defined(CRC32_GENERIC) && defined(CRC32_ARCH_OPTIMIZED)
+static inline bool
+is_arch_extension_supported(void)
+{
+#if defined(HAVE_GETAUXVAL)
+ return (getauxval(AT_HWCAP) & HWCAP_CRC32) != 0;
+
+#elif defined(HAVE_ELF_AUX_INFO)
+ unsigned long feature_flags;
+
+ if (elf_aux_info(AT_HWCAP, &feature_flags, sizeof(feature_flags)) != 0)
+ return false;
+
+ return (feature_flags & HWCAP_CRC32) != 0;
+
+#elif defined(_WIN32)
+ return IsProcessorFeaturePresent(
+ PF_ARM_V8_CRC32_INSTRUCTIONS_AVAILABLE);
+
+#elif defined(__APPLE__) && defined(HAVE_SYSCTLBYNAME)
+ int has_crc32 = 0;
+ size_t size = sizeof(has_crc32);
+
+ // The sysctlbyname() function requires a string identifier for the
+ // CPU feature it tests. The Apple documentation lists the string
+ // "hw.optional.armv8_crc32", which can be found here:
+ // https://developer.apple.com/documentation/kernel/1387446-sysctlbyname/determining_instruction_set_characteristics#3915619
+ if (sysctlbyname("hw.optional.armv8_crc32", &has_crc32,
+ &size, NULL, 0) != 0)
+ return false;
+
+ return has_crc32;
+
+#else
+ // If a runtime detection method cannot be found, then this must
+ // be a compile time error. The checks in crc_common.h should ensure
+ // a runtime detection method is always found if this function is
+ // built. It would be possible to just return false here, but this
+ // is inefficient for binary size and runtime since only the generic
+ // method could ever be used.
+# error Runtime detection method unavailable.
+#endif
+}
+#endif
+
+#endif // LZMA_CRC32_ARM64_H
diff --git a/src/liblzma/check/crc32_fast.c b/src/liblzma/check/crc32_fast.c
index eed7350..16dbb74 100644
--- a/src/liblzma/check/crc32_fast.c
+++ b/src/liblzma/check/crc32_fast.c
@@ -1,35 +1,40 @@
+// SPDX-License-Identifier: 0BSD
+
///////////////////////////////////////////////////////////////////////////////
//
/// \file crc32.c
/// \brief CRC32 calculation
-///
-/// Calculate the CRC32 using the slice-by-eight algorithm.
-/// It is explained in this document:
-/// http://www.intel.com/technology/comms/perfnet/download/CRC_generators.pdf
-/// The code in this file is not the same as in Intel's paper, but
-/// the basic principle is identical.
-//
-// Author: Lasse Collin
//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
+// Authors: Lasse Collin
+// Ilya Kurdyukov
+// Hans Jansen
//
///////////////////////////////////////////////////////////////////////////////
#include "check.h"
-#include "crc_macros.h"
+#include "crc_common.h"
+
+#if defined(CRC_X86_CLMUL)
+# define BUILDING_CRC32_CLMUL
+# include "crc_x86_clmul.h"
+#elif defined(CRC32_ARM64)
+# include "crc32_arm64.h"
+#endif
-// If you make any changes, do some benchmarking! Seemingly unrelated
-// changes can very easily ruin the performance (and very probably is
-// very compiler dependent).
-extern LZMA_API(uint32_t)
-lzma_crc32(const uint8_t *buf, size_t size, uint32_t crc)
+#ifdef CRC32_GENERIC
+
+///////////////////
+// Generic CRC32 //
+///////////////////
+
+static uint32_t
+crc32_generic(const uint8_t *buf, size_t size, uint32_t crc)
{
crc = ~crc;
#ifdef WORDS_BIGENDIAN
- crc = bswap32(crc);
+ crc = byteswap32(crc);
#endif
if (size > 8) {
@@ -75,8 +80,125 @@ lzma_crc32(const uint8_t *buf, size_t size, uint32_t crc)
crc = lzma_crc32_table[0][*buf++ ^ A(crc)] ^ S8(crc);
#ifdef WORDS_BIGENDIAN
- crc = bswap32(crc);
+ crc = byteswap32(crc);
#endif
return ~crc;
}
+#endif
+
+
+#if defined(CRC32_GENERIC) && defined(CRC32_ARCH_OPTIMIZED)
+
+//////////////////////////
+// Function dispatching //
+//////////////////////////
+
+// If both the generic and arch-optimized implementations are built, then
+// the function to use is selected at runtime because the system running
+// the binary might not have the arch-specific instruction set extension(s)
+// available. The dispatch methods in order of priority:
+//
+// 1. Constructor. This method uses __attribute__((__constructor__)) to
+// set crc32_func at load time. This avoids extra computation (and any
+// unlikely threading bugs) on the first call to lzma_crc32() to decide
+// which implementation should be used.
+//
+// 2. First Call Resolution. On the very first call to lzma_crc32(), the
+// call will be directed to crc32_dispatch() instead. This will set the
+// appropriate implementation function and will not be called again.
+// This method does not use any kind of locking but is safe because if
+// multiple threads run the dispatcher simultaneously then they will all
+// set crc32_func to the same value.
+
+typedef uint32_t (*crc32_func_type)(
+ const uint8_t *buf, size_t size, uint32_t crc);
+
+// This resolver is shared between all dispatch methods.
+static crc32_func_type
+crc32_resolve(void)
+{
+ return is_arch_extension_supported()
+ ? &crc32_arch_optimized : &crc32_generic;
+}
+
+
+#ifdef HAVE_FUNC_ATTRIBUTE_CONSTRUCTOR
+// Constructor method.
+# define CRC32_SET_FUNC_ATTR __attribute__((__constructor__))
+static crc32_func_type crc32_func;
+#else
+// First Call Resolution method.
+# define CRC32_SET_FUNC_ATTR
+static uint32_t crc32_dispatch(const uint8_t *buf, size_t size, uint32_t crc);
+static crc32_func_type crc32_func = &crc32_dispatch;
+#endif
+
+CRC32_SET_FUNC_ATTR
+static void
+crc32_set_func(void)
+{
+ crc32_func = crc32_resolve();
+ return;
+}
+
+#ifndef HAVE_FUNC_ATTRIBUTE_CONSTRUCTOR
+static uint32_t
+crc32_dispatch(const uint8_t *buf, size_t size, uint32_t crc)
+{
+ // When __attribute__((__constructor__)) isn't supported, set the
+ // function pointer without any locking. If multiple threads run
+ // the detection code in parallel, they will all end up setting
+ // the pointer to the same value. This avoids the use of
+ // mythread_once() on every call to lzma_crc32() but this likely
+ // isn't strictly standards compliant. Let's change it if it breaks.
+ crc32_set_func();
+ return crc32_func(buf, size, crc);
+}
+
+#endif
+#endif
+
+
+extern LZMA_API(uint32_t)
+lzma_crc32(const uint8_t *buf, size_t size, uint32_t crc)
+{
+#if defined(CRC32_GENERIC) && defined(CRC32_ARCH_OPTIMIZED)
+ // On x86-64, if CLMUL is available, it is the best for non-tiny
+ // inputs, being over twice as fast as the generic slice-by-four
+ // version. However, for size <= 16 it's different. In the extreme
+ // case of size == 1 the generic version can be five times faster.
+ // At size >= 8 the CLMUL starts to become reasonable. It
+ // varies depending on the alignment of buf too.
+ //
+ // The above doesn't include the overhead of mythread_once().
+ // At least on x86-64 GNU/Linux, pthread_once() is very fast but
+ // it still makes lzma_crc32(buf, 1, crc) 50-100 % slower. When
+ // size reaches 12-16 bytes the overhead becomes negligible.
+ //
+ // So using the generic version for size <= 16 may give better
+ // performance with tiny inputs but if such inputs happen rarely
+ // it's not so obvious because then the lookup table of the
+ // generic version may not be in the processor cache.
+#ifdef CRC_USE_GENERIC_FOR_SMALL_INPUTS
+ if (size <= 16)
+ return crc32_generic(buf, size, crc);
+#endif
+
+/*
+#ifndef HAVE_FUNC_ATTRIBUTE_CONSTRUCTOR
+ // See crc32_dispatch(). This would be the alternative which uses
+ // locking and doesn't use crc32_dispatch(). Note that on Windows
+ // this method needs Vista threads.
+ mythread_once(crc64_set_func);
+#endif
+*/
+ return crc32_func(buf, size, crc);
+
+#elif defined(CRC32_ARCH_OPTIMIZED)
+ return crc32_arch_optimized(buf, size, crc);
+
+#else
+ return crc32_generic(buf, size, crc);
+#endif
+}
diff --git a/src/liblzma/check/crc32_small.c b/src/liblzma/check/crc32_small.c
index 186966e..6a1bd66 100644
--- a/src/liblzma/check/crc32_small.c
+++ b/src/liblzma/check/crc32_small.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: 0BSD
+
///////////////////////////////////////////////////////////////////////////////
//
/// \file crc32_small.c
@@ -5,9 +7,6 @@
//
// Author: Lasse Collin
//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
-//
///////////////////////////////////////////////////////////////////////////////
#include "check.h"
diff --git a/src/liblzma/check/crc32_table.c b/src/liblzma/check/crc32_table.c
index b11762a..c141cef 100644
--- a/src/liblzma/check/crc32_table.c
+++ b/src/liblzma/check/crc32_table.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: 0BSD
+
///////////////////////////////////////////////////////////////////////////////
//
/// \file crc32_table.c
@@ -5,18 +7,36 @@
//
// Author: Lasse Collin
//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
-//
///////////////////////////////////////////////////////////////////////////////
#include "common.h"
+
+// FIXME: Compared to crc_common.h this has to check for __x86_64__ too
+// so that in 32-bit builds crc32_x86.S won't break due to a missing table.
+#if defined(HAVE_USABLE_CLMUL) && ((defined(__x86_64__) && defined(__SSSE3__) \
+ && defined(__SSE4_1__) && defined(__PCLMUL__)) \
+ || (defined(__e2k__) && __iset__ >= 6))
+# define NO_CRC32_TABLE
+
+#elif defined(HAVE_ARM64_CRC32) \
+ && !defined(WORDS_BIGENDIAN) \
+ && defined(__ARM_FEATURE_CRC32)
+# define NO_CRC32_TABLE
+#endif
+
+
+#if !defined(HAVE_ENCODERS) && defined(NO_CRC32_TABLE)
+// No table needed. Use a typedef to avoid an empty translation unit.
+typedef void lzma_crc32_dummy;
+
+#else
// Having the declaration here silences clang -Wmissing-variable-declarations.
extern const uint32_t lzma_crc32_table[8][256];
-#ifdef WORDS_BIGENDIAN
-# include "crc32_table_be.h"
-#else
-# include "crc32_table_le.h"
+# ifdef WORDS_BIGENDIAN
+# include "crc32_table_be.h"
+# else
+# include "crc32_table_le.h"
+# endif
#endif
diff --git a/src/liblzma/check/crc32_table_be.h b/src/liblzma/check/crc32_table_be.h
index c483cb6..505c230 100644
--- a/src/liblzma/check/crc32_table_be.h
+++ b/src/liblzma/check/crc32_table_be.h
@@ -1,4 +1,6 @@
-/* This file has been automatically generated by crc32_tablegen.c. */
+// SPDX-License-Identifier: 0BSD
+
+// This file has been generated by crc32_tablegen.c.
const uint32_t lzma_crc32_table[8][256] = {
{
diff --git a/src/liblzma/check/crc32_table_le.h b/src/liblzma/check/crc32_table_le.h
index 25f4fc4..e89c21a 100644
--- a/src/liblzma/check/crc32_table_le.h
+++ b/src/liblzma/check/crc32_table_le.h
@@ -1,4 +1,6 @@
-/* This file has been automatically generated by crc32_tablegen.c. */
+// SPDX-License-Identifier: 0BSD
+
+// This file has been generated by crc32_tablegen.c.
const uint32_t lzma_crc32_table[8][256] = {
{
diff --git a/src/liblzma/check/crc32_tablegen.c b/src/liblzma/check/crc32_tablegen.c
index 31a4d27..b8cf459 100644
--- a/src/liblzma/check/crc32_tablegen.c
+++ b/src/liblzma/check/crc32_tablegen.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: 0BSD
+
///////////////////////////////////////////////////////////////////////////////
//
/// \file crc32_tablegen.c
@@ -9,9 +11,6 @@
//
// Author: Lasse Collin
//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
-//
///////////////////////////////////////////////////////////////////////////////
#include <stdio.h>
@@ -44,7 +43,7 @@ init_crc32_table(void)
#ifdef WORDS_BIGENDIAN
for (size_t s = 0; s < 8; ++s)
for (size_t b = 0; b < 256; ++b)
- crc32_table[s][b] = bswap32(crc32_table[s][b]);
+ crc32_table[s][b] = byteswap32(crc32_table[s][b]);
#endif
return;
@@ -54,9 +53,11 @@ init_crc32_table(void)
static void
print_crc32_table(void)
{
- printf("/* This file has been automatically generated by "
- "crc32_tablegen.c. */\n\n"
- "const uint32_t lzma_crc32_table[8][256] = {\n\t{");
+ // Split the SPDX string so that it won't accidentally match
+ // when tools search for the string.
+ printf("// SPDX" "-License-Identifier" ": 0BSD\n\n"
+ "// This file has been generated by crc32_tablegen.c.\n\n"
+ "const uint32_t lzma_crc32_table[8][256] = {\n\t{");
for (size_t s = 0; s < 8; ++s) {
for (size_t b = 0; b < 256; ++b) {
@@ -82,9 +83,11 @@ print_crc32_table(void)
static void
print_lz_table(void)
{
- printf("/* This file has been automatically generated by "
- "crc32_tablegen.c. */\n\n"
- "const uint32_t lzma_lz_hash_table[256] = {");
+ // Split the SPDX string so that it won't accidentally match
+ // when tools search for the string.
+ printf("// SPDX" "-License-Identifier" ": 0BSD\n\n"
+ "// This file has been generated by crc32_tablegen.c.\n\n"
+ "const uint32_t lzma_lz_hash_table[256] = {");
for (size_t b = 0; b < 256; ++b) {
if ((b % 4) == 0)
diff --git a/src/liblzma/check/crc32_x86.S b/src/liblzma/check/crc32_x86.S
index 4f395df..ddc3cee 100644
--- a/src/liblzma/check/crc32_x86.S
+++ b/src/liblzma/check/crc32_x86.S
@@ -1,3 +1,5 @@
+/* SPDX-License-Identifier: 0BSD */
+
/*
* Speed-optimized CRC32 using slicing-by-eight algorithm
*
@@ -11,9 +13,6 @@
* Authors: Igor Pavlov (original version)
* Lasse Collin (AT&T syntax, PIC support, better portability)
*
- * This file has been put into the public domain.
- * You can do whatever you want with this file.
- *
* This code needs lzma_crc32_table, which can be created using the
* following C code:
diff --git a/src/liblzma/check/crc64_fast.c b/src/liblzma/check/crc64_fast.c
index 0c8622a..0ce83fe 100644
--- a/src/liblzma/check/crc64_fast.c
+++ b/src/liblzma/check/crc64_fast.c
@@ -1,85 +1,30 @@
+// SPDX-License-Identifier: 0BSD
+
///////////////////////////////////////////////////////////////////////////////
//
/// \file crc64.c
/// \brief CRC64 calculation
-///
-/// There are two methods in this file. crc64_generic uses the
-/// the slice-by-four algorithm. This is the same idea that is
-/// used in crc32_fast.c, but for CRC64 we use only four tables
-/// instead of eight to avoid increasing CPU cache usage.
-///
-/// crc64_clmul uses 32/64-bit x86 SSSE3, SSE4.1, and CLMUL instructions.
-/// It was derived from
-/// https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf
-/// and the public domain code from https://github.com/rawrunprotected/crc
-/// (URLs were checked on 2022-11-07).
-///
-/// FIXME: Builds for 32-bit x86 use crc64_x86.S by default instead
-/// of this file and thus CLMUL version isn't available on 32-bit x86
-/// unless configured with --disable-assembler. Even then the lookup table
-/// isn't omitted in crc64_table.c since it doesn't know that assembly
-/// code has been disabled.
//
// Authors: Lasse Collin
// Ilya Kurdyukov
//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
-//
///////////////////////////////////////////////////////////////////////////////
#include "check.h"
+#include "crc_common.h"
-#undef CRC_GENERIC
-#undef CRC_CLMUL
-#undef CRC_USE_GENERIC_FOR_SMALL_INPUTS
-
-// If CLMUL cannot be used then only the generic slice-by-four is built.
-#if !defined(HAVE_USABLE_CLMUL)
-# define CRC_GENERIC 1
-
-// If CLMUL is allowed unconditionally in the compiler options then the
-// generic version can be omitted. Note that this doesn't work with MSVC
-// as I don't know how to detect the features here.
-//
-// NOTE: Keep this this in sync with crc64_table.c.
-#elif (defined(__SSSE3__) && defined(__SSE4_1__) && defined(__PCLMUL__)) \
- || (defined(__e2k__) && __iset__ >= 6)
-# define CRC_CLMUL 1
-
-// Otherwise build both and detect at runtime which version to use.
-#else
-# define CRC_GENERIC 1
-# define CRC_CLMUL 1
-
-/*
- // The generic code is much faster with 1-8-byte inputs and has
- // similar performance up to 16 bytes at least in microbenchmarks
- // (it depends on input buffer alignment too). If both versions are
- // built, this #define will use the generic version for inputs up to
- // 16 bytes and CLMUL for bigger inputs. It saves a little in code
- // size since the special cases for 0-16-byte inputs will be omitted
- // from the CLMUL code.
-# define CRC_USE_GENERIC_FOR_SMALL_INPUTS 1
-*/
-
-# if defined(_MSC_VER)
-# include <intrin.h>
-# elif defined(HAVE_CPUID_H)
-# include <cpuid.h>
-# endif
+#if defined(CRC_X86_CLMUL)
+# define BUILDING_CRC64_CLMUL
+# include "crc_x86_clmul.h"
#endif
+#ifdef CRC64_GENERIC
+
/////////////////////////////////
// Generic slice-by-four CRC64 //
/////////////////////////////////
-#ifdef CRC_GENERIC
-
-#include "crc_macros.h"
-
-
#ifdef WORDS_BIGENDIAN
# define A1(x) ((x) >> 56)
#else
@@ -94,7 +39,7 @@ crc64_generic(const uint8_t *buf, size_t size, uint64_t crc)
crc = ~crc;
#ifdef WORDS_BIGENDIAN
- crc = bswap64(crc);
+ crc = byteswap64(crc);
#endif
if (size > 4) {
@@ -128,7 +73,7 @@ crc64_generic(const uint8_t *buf, size_t size, uint64_t crc)
crc = lzma_crc64_table[0][*buf++ ^ A1(crc)] ^ S8(crc);
#ifdef WORDS_BIGENDIAN
- crc = bswap64(crc);
+ crc = byteswap64(crc);
#endif
return ~crc;
@@ -136,336 +81,40 @@ crc64_generic(const uint8_t *buf, size_t size, uint64_t crc)
#endif
-/////////////////////
-// x86 CLMUL CRC64 //
-/////////////////////
-
-#ifdef CRC_CLMUL
-
-#include <immintrin.h>
-
-
-/*
-// These functions were used to generate the constants
-// at the top of crc64_clmul().
-static uint64_t
-calc_lo(uint64_t poly)
-{
- uint64_t a = poly;
- uint64_t b = 0;
-
- for (unsigned i = 0; i < 64; ++i) {
- b = (b >> 1) | (a << 63);
- a = (a >> 1) ^ (a & 1 ? poly : 0);
- }
-
- return b;
-}
-
-static uint64_t
-calc_hi(uint64_t poly, uint64_t a)
-{
- for (unsigned i = 0; i < 64; ++i)
- a = (a >> 1) ^ (a & 1 ? poly : 0);
-
- return a;
-}
-*/
-
-
-#define MASK_L(in, mask, r) \
- r = _mm_shuffle_epi8(in, mask)
-
-#define MASK_H(in, mask, r) \
- r = _mm_shuffle_epi8(in, _mm_xor_si128(mask, vsign))
-
-#define MASK_LH(in, mask, low, high) \
- MASK_L(in, mask, low); \
- MASK_H(in, mask, high)
-
-
-// MSVC (VS2015 - VS2022) produces bad 32-bit x86 code from the CLMUL CRC
-// code when optimizations are enabled (release build). According to the bug
-// report, the ebx register is corrupted and the calculated result is wrong.
-// Trying to workaround the problem with "__asm mov ebx, ebx" didn't help.
-// The following pragma works and performance is still good. x86-64 builds
-// aren't affected by this problem.
-//
-// NOTE: Another pragma after the function restores the optimizations.
-// If the #if condition here is updated, the other one must be updated too.
-#if defined(_MSC_VER) && !defined(__INTEL_COMPILER) && !defined(__clang__) \
- && defined(_M_IX86)
-# pragma optimize("g", off)
-#endif
-
-// EDG-based compilers (Intel's classic compiler and compiler for E2K) can
-// define __GNUC__ but the attribute must not be used with them.
-// The new Clang-based ICX needs the attribute.
-//
-// NOTE: Build systems check for this too, keep them in sync with this.
-#if (defined(__GNUC__) || defined(__clang__)) && !defined(__EDG__)
-__attribute__((__target__("ssse3,sse4.1,pclmul")))
-#endif
-// The intrinsics use 16-byte-aligned reads from buf, thus they may read
-// up to 15 bytes before or after the buffer (depending on the alignment
-// of the buf argument). The values of the extra bytes are ignored.
-// This unavoidably trips -fsanitize=address so address sanitizier has
-// to be disabled for this function.
-#if lzma_has_attribute(__no_sanitize_address__)
-__attribute__((__no_sanitize_address__))
-#endif
-static uint64_t
-crc64_clmul(const uint8_t *buf, size_t size, uint64_t crc)
-{
- // The prototypes of the intrinsics use signed types while most of
- // the values are treated as unsigned here. These warnings in this
- // function have been checked and found to be harmless so silence them.
-#if TUKLIB_GNUC_REQ(4, 6) || defined(__clang__)
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wsign-conversion"
-# pragma GCC diagnostic ignored "-Wconversion"
-#endif
-
-#ifndef CRC_USE_GENERIC_FOR_SMALL_INPUTS
- // The code assumes that there is at least one byte of input.
- if (size == 0)
- return crc;
-#endif
-
- // const uint64_t poly = 0xc96c5795d7870f42; // CRC polynomial
- const uint64_t p = 0x92d8af2baf0e1e85; // (poly << 1) | 1
- const uint64_t mu = 0x9c3e466c172963d5; // (calc_lo(poly) << 1) | 1
- const uint64_t k2 = 0xdabe95afc7875f40; // calc_hi(poly, 1)
- const uint64_t k1 = 0xe05dd497ca393ae4; // calc_hi(poly, k2)
- const __m128i vfold0 = _mm_set_epi64x(p, mu);
- const __m128i vfold1 = _mm_set_epi64x(k2, k1);
-
- // Create a vector with 8-bit values 0 to 15. This is used to
- // construct control masks for _mm_blendv_epi8 and _mm_shuffle_epi8.
- const __m128i vramp = _mm_setr_epi32(
- 0x03020100, 0x07060504, 0x0b0a0908, 0x0f0e0d0c);
-
- // This is used to inverse the control mask of _mm_shuffle_epi8
- // so that bytes that wouldn't be picked with the original mask
- // will be picked and vice versa.
- const __m128i vsign = _mm_set1_epi8(0x80);
-
- // Memory addresses A to D and the distances between them:
- //
- // A B C D
- // [skip_start][size][skip_end]
- // [ size2 ]
- //
- // A and D are 16-byte aligned. B and C are 1-byte aligned.
- // skip_start and skip_end are 0-15 bytes. size is at least 1 byte.
- //
- // A = aligned_buf will initially point to this address.
- // B = The address pointed by the caller-supplied buf.
- // C = buf + size == aligned_buf + size2
- // D = buf + size + skip_end == aligned_buf + size2 + skip_end
- const size_t skip_start = (size_t)((uintptr_t)buf & 15);
- const size_t skip_end = (size_t)((0U - (uintptr_t)(buf + size)) & 15);
- const __m128i *aligned_buf = (const __m128i *)(
- (uintptr_t)buf & ~(uintptr_t)15);
-
- // If size2 <= 16 then the whole input fits into a single 16-byte
- // vector. If size2 > 16 then at least two 16-byte vectors must
- // be processed. If size2 > 16 && size <= 16 then there is only
- // one 16-byte vector's worth of input but it is unaligned in memory.
- //
- // NOTE: There is no integer overflow here if the arguments are valid.
- // If this overflowed, buf + size would too.
- size_t size2 = skip_start + size;
-
- // Masks to be used with _mm_blendv_epi8 and _mm_shuffle_epi8:
- // The first skip_start or skip_end bytes in the vectors will have
- // the high bit (0x80) set. _mm_blendv_epi8 and _mm_shuffle_epi8
- // will produce zeros for these positions. (Bitwise-xor of these
- // masks with vsign will produce the opposite behavior.)
- const __m128i mask_start
- = _mm_sub_epi8(vramp, _mm_set1_epi8(skip_start));
- const __m128i mask_end = _mm_sub_epi8(vramp, _mm_set1_epi8(skip_end));
-
- // Get the first 1-16 bytes into data0. If loading less than 16 bytes,
- // the bytes are loaded to the high bits of the vector and the least
- // significant positions are filled with zeros.
- const __m128i data0 = _mm_blendv_epi8(_mm_load_si128(aligned_buf),
- _mm_setzero_si128(), mask_start);
- ++aligned_buf;
-
-#if defined(__i386__) || defined(_M_IX86)
- const __m128i initial_crc = _mm_set_epi64x(0, ~crc);
-#else
- // GCC and Clang would produce good code with _mm_set_epi64x
- // but MSVC needs _mm_cvtsi64_si128 on x86-64.
- const __m128i initial_crc = _mm_cvtsi64_si128(~crc);
-#endif
+#if defined(CRC64_GENERIC) && defined(CRC64_ARCH_OPTIMIZED)
- __m128i v0, v1, v2, v3;
-
-#ifndef CRC_USE_GENERIC_FOR_SMALL_INPUTS
- if (size <= 16) {
- // Right-shift initial_crc by 1-16 bytes based on "size"
- // and store the result in v1 (high bytes) and v0 (low bytes).
- //
- // NOTE: The highest 8 bytes of initial_crc are zeros so
- // v1 will be filled with zeros if size >= 8. The highest 8
- // bytes of v1 will always become zeros.
- //
- // [ v1 ][ v0 ]
- // [ initial_crc ] size == 1
- // [ initial_crc ] size == 2
- // [ initial_crc ] size == 15
- // [ initial_crc ] size == 16 (all in v0)
- const __m128i mask_low = _mm_add_epi8(
- vramp, _mm_set1_epi8(size - 16));
- MASK_LH(initial_crc, mask_low, v0, v1);
-
- if (size2 <= 16) {
- // There are 1-16 bytes of input and it is all
- // in data0. Copy the input bytes to v3. If there
- // are fewer than 16 bytes, the low bytes in v3
- // will be filled with zeros. That is, the input
- // bytes are stored to the same position as
- // (part of) initial_crc is in v0.
- MASK_L(data0, mask_end, v3);
- } else {
- // There are 2-16 bytes of input but not all bytes
- // are in data0.
- const __m128i data1 = _mm_load_si128(aligned_buf);
-
- // Collect the 2-16 input bytes from data0 and data1
- // to v2 and v3, and bitwise-xor them with the
- // low bits of initial_crc in v0. Note that the
- // the second xor is below this else-block as it
- // is shared with the other branch.
- MASK_H(data0, mask_end, v2);
- MASK_L(data1, mask_end, v3);
- v0 = _mm_xor_si128(v0, v2);
- }
+//////////////////////////
+// Function dispatching //
+//////////////////////////
- v0 = _mm_xor_si128(v0, v3);
- v1 = _mm_alignr_epi8(v1, v0, 8);
- } else
-#endif
- {
- const __m128i data1 = _mm_load_si128(aligned_buf);
- MASK_LH(initial_crc, mask_start, v0, v1);
- v0 = _mm_xor_si128(v0, data0);
- v1 = _mm_xor_si128(v1, data1);
-
-#define FOLD \
- v1 = _mm_xor_si128(v1, _mm_clmulepi64_si128(v0, vfold1, 0x00)); \
- v0 = _mm_xor_si128(v1, _mm_clmulepi64_si128(v0, vfold1, 0x11));
-
- while (size2 > 32) {
- ++aligned_buf;
- size2 -= 16;
- FOLD
- v1 = _mm_load_si128(aligned_buf);
- }
-
- if (size2 < 32) {
- MASK_H(v0, mask_end, v2);
- MASK_L(v0, mask_end, v0);
- MASK_L(v1, mask_end, v3);
- v1 = _mm_or_si128(v2, v3);
- }
-
- FOLD
- v1 = _mm_srli_si128(v0, 8);
-#undef FOLD
- }
+// If both the generic and arch-optimized implementations are usable, then
+// the function that is used is selected at runtime. See crc32_fast.c.
- v1 = _mm_xor_si128(_mm_clmulepi64_si128(v0, vfold1, 0x10), v1);
- v0 = _mm_clmulepi64_si128(v1, vfold0, 0x00);
- v2 = _mm_clmulepi64_si128(v0, vfold0, 0x10);
- v0 = _mm_xor_si128(_mm_xor_si128(v2, _mm_slli_si128(v0, 8)), v1);
+typedef uint64_t (*crc64_func_type)(
+ const uint8_t *buf, size_t size, uint64_t crc);
-#if defined(__i386__) || defined(_M_IX86)
- return ~(((uint64_t)(uint32_t)_mm_extract_epi32(v0, 3) << 32) |
- (uint64_t)(uint32_t)_mm_extract_epi32(v0, 2));
-#else
- return ~(uint64_t)_mm_extract_epi64(v0, 1);
-#endif
-
-#if TUKLIB_GNUC_REQ(4, 6) || defined(__clang__)
-# pragma GCC diagnostic pop
-#endif
-}
-#if defined(_MSC_VER) && !defined(__INTEL_COMPILER) && !defined(__clang__) \
- && defined(_M_IX86)
-# pragma optimize("", on)
-#endif
-#endif
-
-
-////////////////////////
-// Detect CPU support //
-////////////////////////
-
-#if defined(CRC_GENERIC) && defined(CRC_CLMUL)
-static inline bool
-is_clmul_supported(void)
+static crc64_func_type
+crc64_resolve(void)
{
- int success = 1;
- uint32_t r[4]; // eax, ebx, ecx, edx
-
-#if defined(_MSC_VER)
- // This needs <intrin.h> with MSVC. ICC has it as a built-in
- // on all platforms.
- __cpuid(r, 1);
-#elif defined(HAVE_CPUID_H)
- // Compared to just using __asm__ to run CPUID, this also checks
- // that CPUID is supported and saves and restores ebx as that is
- // needed with GCC < 5 with position-independent code (PIC).
- success = __get_cpuid(1, &r[0], &r[1], &r[2], &r[3]);
-#else
- // Just a fallback that shouldn't be needed.
- __asm__("cpuid\n\t"
- : "=a"(r[0]), "=b"(r[1]), "=c"(r[2]), "=d"(r[3])
- : "a"(1), "c"(0));
-#endif
-
- // Returns true if these are supported:
- // CLMUL (bit 1 in ecx)
- // SSSE3 (bit 9 in ecx)
- // SSE4.1 (bit 19 in ecx)
- const uint32_t ecx_mask = (1 << 1) | (1 << 9) | (1 << 19);
- return success && (r[2] & ecx_mask) == ecx_mask;
-
- // Alternative methods that weren't used:
- // - ICC's _may_i_use_cpu_feature: the other methods should work too.
- // - GCC >= 6 / Clang / ICX __builtin_cpu_supports("pclmul")
- //
- // CPUID decding is needed with MSVC anyway and older GCC. This keeps
- // the feature checks in the build system simpler too. The nice thing
- // about __builtin_cpu_supports would be that it generates very short
- // code as is it only reads a variable set at startup but a few bytes
- // doesn't matter here.
+ return is_arch_extension_supported()
+ ? &crc64_arch_optimized : &crc64_generic;
}
-
#ifdef HAVE_FUNC_ATTRIBUTE_CONSTRUCTOR
-# define CRC64_FUNC_INIT
# define CRC64_SET_FUNC_ATTR __attribute__((__constructor__))
+static crc64_func_type crc64_func;
#else
-# define CRC64_FUNC_INIT = &crc64_dispatch
# define CRC64_SET_FUNC_ATTR
static uint64_t crc64_dispatch(const uint8_t *buf, size_t size, uint64_t crc);
+static crc64_func_type crc64_func = &crc64_dispatch;
#endif
-// Pointer to the the selected CRC64 method.
-static uint64_t (*crc64_func)(const uint8_t *buf, size_t size, uint64_t crc)
- CRC64_FUNC_INIT;
-
-
CRC64_SET_FUNC_ATTR
static void
crc64_set_func(void)
{
- crc64_func = is_clmul_supported() ? &crc64_clmul : &crc64_generic;
+ crc64_func = crc64_resolve();
return;
}
@@ -474,12 +123,6 @@ crc64_set_func(void)
static uint64_t
crc64_dispatch(const uint8_t *buf, size_t size, uint64_t crc)
{
- // When __attribute__((__constructor__)) isn't supported, set the
- // function pointer without any locking. If multiple threads run
- // the detection code in parallel, they will all end up setting
- // the pointer to the same value. This avoids the use of
- // mythread_once() on every call to lzma_crc64() but this likely
- // isn't strictly standards compliant. Let's change it if it breaks.
crc64_set_func();
return crc64_func(buf, size, crc);
}
@@ -490,47 +133,22 @@ crc64_dispatch(const uint8_t *buf, size_t size, uint64_t crc)
extern LZMA_API(uint64_t)
lzma_crc64(const uint8_t *buf, size_t size, uint64_t crc)
{
-#if defined(CRC_GENERIC) && defined(CRC_CLMUL)
- // If CLMUL is available, it is the best for non-tiny inputs,
- // being over twice as fast as the generic slice-by-four version.
- // However, for size <= 16 it's different. In the extreme case
- // of size == 1 the generic version can be five times faster.
- // At size >= 8 the CLMUL starts to become reasonable. It
- // varies depending on the alignment of buf too.
- //
- // The above doesn't include the overhead of mythread_once().
- // At least on x86-64 GNU/Linux, pthread_once() is very fast but
- // it still makes lzma_crc64(buf, 1, crc) 50-100 % slower. When
- // size reaches 12-16 bytes the overhead becomes negligible.
- //
- // So using the generic version for size <= 16 may give better
- // performance with tiny inputs but if such inputs happen rarely
- // it's not so obvious because then the lookup table of the
- // generic version may not be in the processor cache.
+#if defined(CRC64_GENERIC) && defined(CRC64_ARCH_OPTIMIZED)
+
#ifdef CRC_USE_GENERIC_FOR_SMALL_INPUTS
if (size <= 16)
return crc64_generic(buf, size, crc);
#endif
-
-/*
-#ifndef HAVE_FUNC_ATTRIBUTE_CONSTRUCTOR
- // See crc64_dispatch(). This would be the alternative which uses
- // locking and doesn't use crc64_dispatch(). Note that on Windows
- // this method needs Vista threads.
- mythread_once(crc64_set_func);
-#endif
-*/
-
return crc64_func(buf, size, crc);
-#elif defined(CRC_CLMUL)
- // If CLMUL is used unconditionally without runtime CPU detection
- // then omitting the generic version and its 8 KiB lookup table
- // makes the library smaller.
+#elif defined(CRC64_ARCH_OPTIMIZED)
+ // If arch-optimized version is used unconditionally without runtime
+ // CPU detection then omitting the generic version and its 8 KiB
+ // lookup table makes the library smaller.
//
// FIXME: Lookup table isn't currently omitted on 32-bit x86,
// see crc64_table.c.
- return crc64_clmul(buf, size, crc);
+ return crc64_arch_optimized(buf, size, crc);
#else
return crc64_generic(buf, size, crc);
diff --git a/src/liblzma/check/crc64_small.c b/src/liblzma/check/crc64_small.c
index 420f7cf..ee4ea26 100644
--- a/src/liblzma/check/crc64_small.c
+++ b/src/liblzma/check/crc64_small.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: 0BSD
+
///////////////////////////////////////////////////////////////////////////////
//
/// \file crc64_small.c
@@ -5,9 +7,6 @@
//
// Author: Lasse Collin
//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
-//
///////////////////////////////////////////////////////////////////////////////
#include "check.h"
diff --git a/src/liblzma/check/crc64_table.c b/src/liblzma/check/crc64_table.c
index 688e527..78e4275 100644
--- a/src/liblzma/check/crc64_table.c
+++ b/src/liblzma/check/crc64_table.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: 0BSD
+
///////////////////////////////////////////////////////////////////////////////
//
/// \file crc64_table.c
@@ -5,19 +7,21 @@
//
// Author: Lasse Collin
//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
-//
///////////////////////////////////////////////////////////////////////////////
#include "common.h"
-// FIXME: Compared to crc64_fast.c this has to check for __x86_64__ too
+// FIXME: Compared to crc_common.h this has to check for __x86_64__ too
// so that in 32-bit builds crc64_x86.S won't break due to a missing table.
-#if (defined(__x86_64__) && defined(__SSSE3__) \
+#if defined(HAVE_USABLE_CLMUL) && ((defined(__x86_64__) && defined(__SSSE3__) \
&& defined(__SSE4_1__) && defined(__PCLMUL__)) \
- || (defined(__e2k__) && __iset__ >= 6)
+ || (defined(__e2k__) && __iset__ >= 6))
+# define NO_CRC64_TABLE
+#endif
+
+
+#ifdef NO_CRC64_TABLE
// No table needed. Use a typedef to avoid an empty translation unit.
typedef void lzma_crc64_dummy;
diff --git a/src/liblzma/check/crc64_table_be.h b/src/liblzma/check/crc64_table_be.h
index ea074f3..db76cc7 100644
--- a/src/liblzma/check/crc64_table_be.h
+++ b/src/liblzma/check/crc64_table_be.h
@@ -1,4 +1,6 @@
-/* This file has been automatically generated by crc64_tablegen.c. */
+// SPDX-License-Identifier: 0BSD
+
+// This file has been generated by crc64_tablegen.c.
const uint64_t lzma_crc64_table[4][256] = {
{
diff --git a/src/liblzma/check/crc64_table_le.h b/src/liblzma/check/crc64_table_le.h
index 1196b31..e40a8c8 100644
--- a/src/liblzma/check/crc64_table_le.h
+++ b/src/liblzma/check/crc64_table_le.h
@@ -1,4 +1,6 @@
-/* This file has been automatically generated by crc64_tablegen.c. */
+// SPDX-License-Identifier: 0BSD
+
+// This file has been generated by crc64_tablegen.c.
const uint64_t lzma_crc64_table[4][256] = {
{
diff --git a/src/liblzma/check/crc64_tablegen.c b/src/liblzma/check/crc64_tablegen.c
index fddaa7e..2035127 100644
--- a/src/liblzma/check/crc64_tablegen.c
+++ b/src/liblzma/check/crc64_tablegen.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: 0BSD
+
///////////////////////////////////////////////////////////////////////////////
//
/// \file crc64_tablegen.c
@@ -8,9 +10,6 @@
//
// Author: Lasse Collin
//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
-//
///////////////////////////////////////////////////////////////////////////////
#include <stdio.h>
@@ -43,7 +42,7 @@ init_crc64_table(void)
#ifdef WORDS_BIGENDIAN
for (size_t s = 0; s < 4; ++s)
for (size_t b = 0; b < 256; ++b)
- crc64_table[s][b] = bswap64(crc64_table[s][b]);
+ crc64_table[s][b] = byteswap64(crc64_table[s][b]);
#endif
return;
@@ -53,9 +52,11 @@ init_crc64_table(void)
static void
print_crc64_table(void)
{
- printf("/* This file has been automatically generated by "
- "crc64_tablegen.c. */\n\n"
- "const uint64_t lzma_crc64_table[4][256] = {\n\t{");
+ // Split the SPDX string so that it won't accidentally match
+ // when tools search for the string.
+ printf("// SPDX" "-License-Identifier" ": 0BSD\n\n"
+ "// This file has been generated by crc64_tablegen.c.\n\n"
+ "const uint64_t lzma_crc64_table[4][256] = {\n\t{");
for (size_t s = 0; s < 4; ++s) {
for (size_t b = 0; b < 256; ++b) {
diff --git a/src/liblzma/check/crc64_x86.S b/src/liblzma/check/crc64_x86.S
index 9aecf58..47f6081 100644
--- a/src/liblzma/check/crc64_x86.S
+++ b/src/liblzma/check/crc64_x86.S
@@ -1,3 +1,5 @@
+/* SPDX-License-Identifier: 0BSD */
+
/*
* Speed-optimized CRC64 using slicing-by-four algorithm
*
@@ -7,9 +9,6 @@
* Authors: Igor Pavlov (original CRC32 assembly code)
* Lasse Collin (CRC64 adaptation of the modified CRC32 code)
*
- * This file has been put into the public domain.
- * You can do whatever you want with this file.
- *
* This code needs lzma_crc64_table, which can be created using the
* following C code:
diff --git a/src/liblzma/check/crc_common.h b/src/liblzma/check/crc_common.h
new file mode 100644
index 0000000..63a7b5c
--- /dev/null
+++ b/src/liblzma/check/crc_common.h
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: 0BSD
+
+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file crc_common.h
+/// \brief Some functions and macros for CRC32 and CRC64
+//
+// Authors: Lasse Collin
+// Ilya Kurdyukov
+// Hans Jansen
+// Jia Tan
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#ifndef LZMA_CRC_COMMON_H
+#define LZMA_CRC_COMMON_H
+
+#include "common.h"
+
+
+#ifdef WORDS_BIGENDIAN
+# define A(x) ((x) >> 24)
+# define B(x) (((x) >> 16) & 0xFF)
+# define C(x) (((x) >> 8) & 0xFF)
+# define D(x) ((x) & 0xFF)
+
+# define S8(x) ((x) << 8)
+# define S32(x) ((x) << 32)
+
+#else
+# define A(x) ((x) & 0xFF)
+# define B(x) (((x) >> 8) & 0xFF)
+# define C(x) (((x) >> 16) & 0xFF)
+# define D(x) ((x) >> 24)
+
+# define S8(x) ((x) >> 8)
+# define S32(x) ((x) >> 32)
+#endif
+
+
+// CRC CLMUL code needs this because accessing input buffers that aren't
+// aligned to the vector size will inherently trip the address sanitizer.
+#if lzma_has_attribute(__no_sanitize_address__)
+# define crc_attr_no_sanitize_address \
+ __attribute__((__no_sanitize_address__))
+#else
+# define crc_attr_no_sanitize_address
+#endif
+
+// Keep this in sync with changes to crc32_arm64.h
+#if defined(_WIN32) || defined(HAVE_GETAUXVAL) \
+ || defined(HAVE_ELF_AUX_INFO) \
+ || (defined(__APPLE__) && defined(HAVE_SYSCTLBYNAME))
+# define ARM64_RUNTIME_DETECTION 1
+#endif
+
+
+#undef CRC32_GENERIC
+#undef CRC64_GENERIC
+
+#undef CRC32_ARCH_OPTIMIZED
+#undef CRC64_ARCH_OPTIMIZED
+
+// The x86 CLMUL is used for both CRC32 and CRC64.
+#undef CRC_X86_CLMUL
+
+#undef CRC32_ARM64
+#undef CRC64_ARM64_CLMUL
+
+#undef CRC_USE_GENERIC_FOR_SMALL_INPUTS
+
+// ARM64 CRC32 instruction is only useful for CRC32. Currently, only
+// little endian is supported since we were unable to test on a big
+// endian machine.
+//
+// NOTE: Keep this and the next check in sync with the macro
+// NO_CRC32_TABLE in crc32_table.c
+#if defined(HAVE_ARM64_CRC32) && !defined(WORDS_BIGENDIAN)
+// Allow ARM64 CRC32 instruction without a runtime check if
+// __ARM_FEATURE_CRC32 is defined. GCC and Clang only define this if the
+// proper compiler options are used.
+# if defined(__ARM_FEATURE_CRC32)
+# define CRC32_ARCH_OPTIMIZED 1
+# define CRC32_ARM64 1
+# elif defined(ARM64_RUNTIME_DETECTION)
+# define CRC32_ARCH_OPTIMIZED 1
+# define CRC32_ARM64 1
+# define CRC32_GENERIC 1
+# endif
+#endif
+
+#if defined(HAVE_USABLE_CLMUL)
+// If CLMUL is allowed unconditionally in the compiler options then the
+// generic version can be omitted. Note that this doesn't work with MSVC
+// as I don't know how to detect the features here.
+//
+// NOTE: Keep this in sync with the NO_CRC32_TABLE macro in crc32_table.c
+// and NO_CRC64_TABLE in crc64_table.c.
+# if (defined(__SSSE3__) && defined(__SSE4_1__) && defined(__PCLMUL__)) \
+ || (defined(__e2k__) && __iset__ >= 6)
+# define CRC32_ARCH_OPTIMIZED 1
+# define CRC64_ARCH_OPTIMIZED 1
+# define CRC_X86_CLMUL 1
+# else
+# define CRC32_GENERIC 1
+# define CRC64_GENERIC 1
+# define CRC32_ARCH_OPTIMIZED 1
+# define CRC64_ARCH_OPTIMIZED 1
+# define CRC_X86_CLMUL 1
+
+/*
+ // The generic code is much faster with 1-8-byte inputs and
+ // has similar performance up to 16 bytes at least in
+ // microbenchmarks (it depends on input buffer alignment
+ // too). If both versions are built, this #define will use
+ // the generic version for inputs up to 16 bytes and CLMUL
+ // for bigger inputs. It saves a little in code size since
+ // the special cases for 0-16-byte inputs will be omitted
+ // from the CLMUL code.
+# define CRC_USE_GENERIC_FOR_SMALL_INPUTS 1
+*/
+# endif
+#endif
+
+// For CRC32 use the generic slice-by-eight implementation if no optimized
+// version is available.
+#if !defined(CRC32_ARCH_OPTIMIZED) && !defined(CRC32_GENERIC)
+# define CRC32_GENERIC 1
+#endif
+
+// For CRC64 use the generic slice-by-four implementation if no optimized
+// version is available.
+#if !defined(CRC64_ARCH_OPTIMIZED) && !defined(CRC64_GENERIC)
+# define CRC64_GENERIC 1
+#endif
+
+#endif
diff --git a/src/liblzma/check/crc_macros.h b/src/liblzma/check/crc_macros.h
deleted file mode 100644
index a7c21b7..0000000
--- a/src/liblzma/check/crc_macros.h
+++ /dev/null
@@ -1,30 +0,0 @@
-///////////////////////////////////////////////////////////////////////////////
-//
-/// \file crc_macros.h
-/// \brief Some endian-dependent macros for CRC32 and CRC64
-//
-// Author: Lasse Collin
-//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
-//
-///////////////////////////////////////////////////////////////////////////////
-
-#ifdef WORDS_BIGENDIAN
-# define A(x) ((x) >> 24)
-# define B(x) (((x) >> 16) & 0xFF)
-# define C(x) (((x) >> 8) & 0xFF)
-# define D(x) ((x) & 0xFF)
-
-# define S8(x) ((x) << 8)
-# define S32(x) ((x) << 32)
-
-#else
-# define A(x) ((x) & 0xFF)
-# define B(x) (((x) >> 8) & 0xFF)
-# define C(x) (((x) >> 16) & 0xFF)
-# define D(x) ((x) >> 24)
-
-# define S8(x) ((x) >> 8)
-# define S32(x) ((x) >> 32)
-#endif
diff --git a/src/liblzma/check/crc_x86_clmul.h b/src/liblzma/check/crc_x86_clmul.h
new file mode 100644
index 0000000..f1254ec
--- /dev/null
+++ b/src/liblzma/check/crc_x86_clmul.h
@@ -0,0 +1,428 @@
+// SPDX-License-Identifier: 0BSD
+
+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file crc_x86_clmul.h
+/// \brief CRC32 and CRC64 implementations using CLMUL instructions.
+///
+/// The CRC32 and CRC64 implementations use 32/64-bit x86 SSSE3, SSE4.1, and
+/// CLMUL instructions. This is compatible with Elbrus 2000 (E2K) too.
+///
+/// They were derived from
+/// https://www.researchgate.net/publication/263424619_Fast_CRC_computation
+/// and the public domain code from https://github.com/rawrunprotected/crc
+/// (URLs were checked on 2023-10-14).
+///
+/// While this file has both CRC32 and CRC64 implementations, only one
+/// should be built at a time to ensure that crc_simd_body() is inlined
+/// even with compilers with which lzma_always_inline expands to plain inline.
+/// The version to build is selected by defining BUILDING_CRC32_CLMUL or
+/// BUILDING_CRC64_CLMUL before including this file.
+///
+/// FIXME: Builds for 32-bit x86 use the assembly .S files by default
+/// unless configured with --disable-assembler. Even then the lookup table
+/// isn't omitted in crc64_table.c since it doesn't know that assembly
+/// code has been disabled.
+//
+// Authors: Ilya Kurdyukov
+// Hans Jansen
+// Lasse Collin
+// Jia Tan
+//
+///////////////////////////////////////////////////////////////////////////////
+
+// This file must not be included more than once.
+#ifdef LZMA_CRC_X86_CLMUL_H
+# error crc_x86_clmul.h was included twice.
+#endif
+#define LZMA_CRC_X86_CLMUL_H
+
+#include <immintrin.h>
+
+#if defined(_MSC_VER)
+# include <intrin.h>
+#elif defined(HAVE_CPUID_H)
+# include <cpuid.h>
+#endif
+
+
+// EDG-based compilers (Intel's classic compiler and compiler for E2K) can
+// define __GNUC__ but the attribute must not be used with them.
+// The new Clang-based ICX needs the attribute.
+//
+// NOTE: Build systems check for this too, keep them in sync with this.
+#if (defined(__GNUC__) || defined(__clang__)) && !defined(__EDG__)
+# define crc_attr_target \
+ __attribute__((__target__("ssse3,sse4.1,pclmul")))
+#else
+# define crc_attr_target
+#endif
+
+
+#define MASK_L(in, mask, r) r = _mm_shuffle_epi8(in, mask)
+
+#define MASK_H(in, mask, r) \
+ r = _mm_shuffle_epi8(in, _mm_xor_si128(mask, vsign))
+
+#define MASK_LH(in, mask, low, high) \
+ MASK_L(in, mask, low); \
+ MASK_H(in, mask, high)
+
+
+crc_attr_target
+crc_attr_no_sanitize_address
+static lzma_always_inline void
+crc_simd_body(const uint8_t *buf, const size_t size, __m128i *v0, __m128i *v1,
+ const __m128i vfold16, const __m128i initial_crc)
+{
+ // Create a vector with 8-bit values 0 to 15. This is used to
+ // construct control masks for _mm_blendv_epi8 and _mm_shuffle_epi8.
+ const __m128i vramp = _mm_setr_epi32(
+ 0x03020100, 0x07060504, 0x0b0a0908, 0x0f0e0d0c);
+
+ // This is used to inverse the control mask of _mm_shuffle_epi8
+ // so that bytes that wouldn't be picked with the original mask
+ // will be picked and vice versa.
+ const __m128i vsign = _mm_set1_epi8(-0x80);
+
+ // Memory addresses A to D and the distances between them:
+ //
+ // A B C D
+ // [skip_start][size][skip_end]
+ // [ size2 ]
+ //
+ // A and D are 16-byte aligned. B and C are 1-byte aligned.
+ // skip_start and skip_end are 0-15 bytes. size is at least 1 byte.
+ //
+ // A = aligned_buf will initially point to this address.
+ // B = The address pointed by the caller-supplied buf.
+ // C = buf + size == aligned_buf + size2
+ // D = buf + size + skip_end == aligned_buf + size2 + skip_end
+ const size_t skip_start = (size_t)((uintptr_t)buf & 15);
+ const size_t skip_end = (size_t)((0U - (uintptr_t)(buf + size)) & 15);
+ const __m128i *aligned_buf = (const __m128i *)(
+ (uintptr_t)buf & ~(uintptr_t)15);
+
+ // If size2 <= 16 then the whole input fits into a single 16-byte
+ // vector. If size2 > 16 then at least two 16-byte vectors must
+ // be processed. If size2 > 16 && size <= 16 then there is only
+ // one 16-byte vector's worth of input but it is unaligned in memory.
+ //
+ // NOTE: There is no integer overflow here if the arguments
+ // are valid. If this overflowed, buf + size would too.
+ const size_t size2 = skip_start + size;
+
+ // Masks to be used with _mm_blendv_epi8 and _mm_shuffle_epi8:
+ // The first skip_start or skip_end bytes in the vectors will have
+ // the high bit (0x80) set. _mm_blendv_epi8 and _mm_shuffle_epi8
+ // will produce zeros for these positions. (Bitwise-xor of these
+ // masks with vsign will produce the opposite behavior.)
+ const __m128i mask_start
+ = _mm_sub_epi8(vramp, _mm_set1_epi8((char)skip_start));
+ const __m128i mask_end
+ = _mm_sub_epi8(vramp, _mm_set1_epi8((char)skip_end));
+
+ // Get the first 1-16 bytes into data0. If loading less than 16
+ // bytes, the bytes are loaded to the high bits of the vector and
+ // the least significant positions are filled with zeros.
+ const __m128i data0 = _mm_blendv_epi8(_mm_load_si128(aligned_buf),
+ _mm_setzero_si128(), mask_start);
+ aligned_buf++;
+
+ __m128i v2, v3;
+
+#ifndef CRC_USE_GENERIC_FOR_SMALL_INPUTS
+ if (size <= 16) {
+ // Right-shift initial_crc by 1-16 bytes based on "size"
+ // and store the result in v1 (high bytes) and v0 (low bytes).
+ //
+ // NOTE: The highest 8 bytes of initial_crc are zeros so
+ // v1 will be filled with zeros if size >= 8. The highest
+ // 8 bytes of v1 will always become zeros.
+ //
+ // [ v1 ][ v0 ]
+ // [ initial_crc ] size == 1
+ // [ initial_crc ] size == 2
+ // [ initial_crc ] size == 15
+ // [ initial_crc ] size == 16 (all in v0)
+ const __m128i mask_low = _mm_add_epi8(
+ vramp, _mm_set1_epi8((char)(size - 16)));
+ MASK_LH(initial_crc, mask_low, *v0, *v1);
+
+ if (size2 <= 16) {
+ // There are 1-16 bytes of input and it is all
+ // in data0. Copy the input bytes to v3. If there
+ // are fewer than 16 bytes, the low bytes in v3
+ // will be filled with zeros. That is, the input
+ // bytes are stored to the same position as
+ // (part of) initial_crc is in v0.
+ MASK_L(data0, mask_end, v3);
+ } else {
+ // There are 2-16 bytes of input but not all bytes
+ // are in data0.
+ const __m128i data1 = _mm_load_si128(aligned_buf);
+
+ // Collect the 2-16 input bytes from data0 and data1
+ // to v2 and v3, and bitwise-xor them with the
+ // low bits of initial_crc in v0. Note that the
+ // the second xor is below this else-block as it
+ // is shared with the other branch.
+ MASK_H(data0, mask_end, v2);
+ MASK_L(data1, mask_end, v3);
+ *v0 = _mm_xor_si128(*v0, v2);
+ }
+
+ *v0 = _mm_xor_si128(*v0, v3);
+ *v1 = _mm_alignr_epi8(*v1, *v0, 8);
+ } else
+#endif
+ {
+ // There is more than 16 bytes of input.
+ const __m128i data1 = _mm_load_si128(aligned_buf);
+ const __m128i *end = (const __m128i*)(
+ (const char *)aligned_buf - 16 + size2);
+ aligned_buf++;
+
+ MASK_LH(initial_crc, mask_start, *v0, *v1);
+ *v0 = _mm_xor_si128(*v0, data0);
+ *v1 = _mm_xor_si128(*v1, data1);
+
+ while (aligned_buf < end) {
+ *v1 = _mm_xor_si128(*v1, _mm_clmulepi64_si128(
+ *v0, vfold16, 0x00));
+ *v0 = _mm_xor_si128(*v1, _mm_clmulepi64_si128(
+ *v0, vfold16, 0x11));
+ *v1 = _mm_load_si128(aligned_buf++);
+ }
+
+ if (aligned_buf != end) {
+ MASK_H(*v0, mask_end, v2);
+ MASK_L(*v0, mask_end, *v0);
+ MASK_L(*v1, mask_end, v3);
+ *v1 = _mm_or_si128(v2, v3);
+ }
+
+ *v1 = _mm_xor_si128(*v1, _mm_clmulepi64_si128(
+ *v0, vfold16, 0x00));
+ *v0 = _mm_xor_si128(*v1, _mm_clmulepi64_si128(
+ *v0, vfold16, 0x11));
+ *v1 = _mm_srli_si128(*v0, 8);
+ }
+}
+
+
+/////////////////////
+// x86 CLMUL CRC32 //
+/////////////////////
+
+/*
+// These functions were used to generate the constants
+// at the top of crc32_arch_optimized().
+static uint64_t
+calc_lo(uint64_t p, uint64_t a, int n)
+{
+ uint64_t b = 0; int i;
+ for (i = 0; i < n; i++) {
+ b = b >> 1 | (a & 1) << (n - 1);
+ a = (a >> 1) ^ ((0 - (a & 1)) & p);
+ }
+ return b;
+}
+
+// same as ~crc(&a, sizeof(a), ~0)
+static uint64_t
+calc_hi(uint64_t p, uint64_t a, int n)
+{
+ int i;
+ for (i = 0; i < n; i++)
+ a = (a >> 1) ^ ((0 - (a & 1)) & p);
+ return a;
+}
+*/
+
+#ifdef BUILDING_CRC32_CLMUL
+
+crc_attr_target
+crc_attr_no_sanitize_address
+static uint32_t
+crc32_arch_optimized(const uint8_t *buf, size_t size, uint32_t crc)
+{
+#ifndef CRC_USE_GENERIC_FOR_SMALL_INPUTS
+ // The code assumes that there is at least one byte of input.
+ if (size == 0)
+ return crc;
+#endif
+
+ // uint32_t poly = 0xedb88320;
+ const int64_t p = 0x1db710640; // p << 1
+ const int64_t mu = 0x1f7011641; // calc_lo(p, p, 32) << 1 | 1
+ const int64_t k5 = 0x163cd6124; // calc_hi(p, p, 32) << 1
+ const int64_t k4 = 0x0ccaa009e; // calc_hi(p, p, 64) << 1
+ const int64_t k3 = 0x1751997d0; // calc_hi(p, p, 128) << 1
+
+ const __m128i vfold4 = _mm_set_epi64x(mu, p);
+ const __m128i vfold8 = _mm_set_epi64x(0, k5);
+ const __m128i vfold16 = _mm_set_epi64x(k4, k3);
+
+ __m128i v0, v1, v2;
+
+ crc_simd_body(buf, size, &v0, &v1, vfold16,
+ _mm_cvtsi32_si128((int32_t)~crc));
+
+ v1 = _mm_xor_si128(
+ _mm_clmulepi64_si128(v0, vfold16, 0x10), v1); // xxx0
+ v2 = _mm_shuffle_epi32(v1, 0xe7); // 0xx0
+ v0 = _mm_slli_epi64(v1, 32); // [0]
+ v0 = _mm_clmulepi64_si128(v0, vfold8, 0x00);
+ v0 = _mm_xor_si128(v0, v2); // [1] [2]
+ v2 = _mm_clmulepi64_si128(v0, vfold4, 0x10);
+ v2 = _mm_clmulepi64_si128(v2, vfold4, 0x00);
+ v0 = _mm_xor_si128(v0, v2); // [2]
+ return ~(uint32_t)_mm_extract_epi32(v0, 2);
+}
+#endif // BUILDING_CRC32_CLMUL
+
+
+/////////////////////
+// x86 CLMUL CRC64 //
+/////////////////////
+
+/*
+// These functions were used to generate the constants
+// at the top of crc64_arch_optimized().
+static uint64_t
+calc_lo(uint64_t poly)
+{
+ uint64_t a = poly;
+ uint64_t b = 0;
+
+ for (unsigned i = 0; i < 64; ++i) {
+ b = (b >> 1) | (a << 63);
+ a = (a >> 1) ^ (a & 1 ? poly : 0);
+ }
+
+ return b;
+}
+
+static uint64_t
+calc_hi(uint64_t poly, uint64_t a)
+{
+ for (unsigned i = 0; i < 64; ++i)
+ a = (a >> 1) ^ (a & 1 ? poly : 0);
+
+ return a;
+}
+*/
+
+#ifdef BUILDING_CRC64_CLMUL
+
+// MSVC (VS2015 - VS2022) produces bad 32-bit x86 code from the CLMUL CRC
+// code when optimizations are enabled (release build). According to the bug
+// report, the ebx register is corrupted and the calculated result is wrong.
+// Trying to workaround the problem with "__asm mov ebx, ebx" didn't help.
+// The following pragma works and performance is still good. x86-64 builds
+// and CRC32 CLMUL aren't affected by this problem. The problem does not
+// happen in crc_simd_body() either (which is shared with CRC32 CLMUL anyway).
+//
+// NOTE: Another pragma after crc64_arch_optimized() restores
+// the optimizations. If the #if condition here is updated,
+// the other one must be updated too.
+#if defined(_MSC_VER) && !defined(__INTEL_COMPILER) && !defined(__clang__) \
+ && defined(_M_IX86)
+# pragma optimize("g", off)
+#endif
+
+crc_attr_target
+crc_attr_no_sanitize_address
+static uint64_t
+crc64_arch_optimized(const uint8_t *buf, size_t size, uint64_t crc)
+{
+#ifndef CRC_USE_GENERIC_FOR_SMALL_INPUTS
+ // The code assumes that there is at least one byte of input.
+ if (size == 0)
+ return crc;
+#endif
+
+ // const uint64_t poly = 0xc96c5795d7870f42; // CRC polynomial
+ const uint64_t p = 0x92d8af2baf0e1e85; // (poly << 1) | 1
+ const uint64_t mu = 0x9c3e466c172963d5; // (calc_lo(poly) << 1) | 1
+ const uint64_t k2 = 0xdabe95afc7875f40; // calc_hi(poly, 1)
+ const uint64_t k1 = 0xe05dd497ca393ae4; // calc_hi(poly, k2)
+
+ const __m128i vfold8 = _mm_set_epi64x((int64_t)p, (int64_t)mu);
+ const __m128i vfold16 = _mm_set_epi64x((int64_t)k2, (int64_t)k1);
+
+ __m128i v0, v1, v2;
+
+#if defined(__i386__) || defined(_M_IX86)
+ crc_simd_body(buf, size, &v0, &v1, vfold16,
+ _mm_set_epi64x(0, (int64_t)~crc));
+#else
+ // GCC and Clang would produce good code with _mm_set_epi64x
+ // but MSVC needs _mm_cvtsi64_si128 on x86-64.
+ crc_simd_body(buf, size, &v0, &v1, vfold16,
+ _mm_cvtsi64_si128((int64_t)~crc));
+#endif
+
+ v1 = _mm_xor_si128(_mm_clmulepi64_si128(v0, vfold16, 0x10), v1);
+ v0 = _mm_clmulepi64_si128(v1, vfold8, 0x00);
+ v2 = _mm_clmulepi64_si128(v0, vfold8, 0x10);
+ v0 = _mm_xor_si128(_mm_xor_si128(v1, _mm_slli_si128(v0, 8)), v2);
+
+#if defined(__i386__) || defined(_M_IX86)
+ return ~(((uint64_t)(uint32_t)_mm_extract_epi32(v0, 3) << 32) |
+ (uint64_t)(uint32_t)_mm_extract_epi32(v0, 2));
+#else
+ return ~(uint64_t)_mm_extract_epi64(v0, 1);
+#endif
+}
+
+#if defined(_MSC_VER) && !defined(__INTEL_COMPILER) && !defined(__clang__) \
+ && defined(_M_IX86)
+# pragma optimize("", on)
+#endif
+
+#endif // BUILDING_CRC64_CLMUL
+
+
+// Inlining this function duplicates the function body in crc32_resolve() and
+// crc64_resolve(), but this is acceptable because this is a tiny function.
+static inline bool
+is_arch_extension_supported(void)
+{
+ int success = 1;
+ uint32_t r[4]; // eax, ebx, ecx, edx
+
+#if defined(_MSC_VER)
+ // This needs <intrin.h> with MSVC. ICC has it as a built-in
+ // on all platforms.
+ __cpuid(r, 1);
+#elif defined(HAVE_CPUID_H)
+ // Compared to just using __asm__ to run CPUID, this also checks
+ // that CPUID is supported and saves and restores ebx as that is
+ // needed with GCC < 5 with position-independent code (PIC).
+ success = __get_cpuid(1, &r[0], &r[1], &r[2], &r[3]);
+#else
+ // Just a fallback that shouldn't be needed.
+ __asm__("cpuid\n\t"
+ : "=a"(r[0]), "=b"(r[1]), "=c"(r[2]), "=d"(r[3])
+ : "a"(1), "c"(0));
+#endif
+
+ // Returns true if these are supported:
+ // CLMUL (bit 1 in ecx)
+ // SSSE3 (bit 9 in ecx)
+ // SSE4.1 (bit 19 in ecx)
+ const uint32_t ecx_mask = (1 << 1) | (1 << 9) | (1 << 19);
+ return success && (r[2] & ecx_mask) == ecx_mask;
+
+ // Alternative methods that weren't used:
+ // - ICC's _may_i_use_cpu_feature: the other methods should work too.
+ // - GCC >= 6 / Clang / ICX __builtin_cpu_supports("pclmul")
+ //
+ // CPUID decding is needed with MSVC anyway and older GCC. This keeps
+ // the feature checks in the build system simpler too. The nice thing
+ // about __builtin_cpu_supports would be that it generates very short
+ // code as is it only reads a variable set at startup but a few bytes
+ // doesn't matter here.
+}
diff --git a/src/liblzma/check/sha256.c b/src/liblzma/check/sha256.c
index 6feb342..bd0d280 100644
--- a/src/liblzma/check/sha256.c
+++ b/src/liblzma/check/sha256.c
@@ -1,24 +1,17 @@
+// SPDX-License-Identifier: 0BSD
+
///////////////////////////////////////////////////////////////////////////////
//
/// \file sha256.c
/// \brief SHA-256
-///
-/// \todo Crypto++ has x86 ASM optimizations. They use SSE so if they
-/// are imported to liblzma, SSE instructions need to be used
-/// conditionally to keep the code working on older boxes.
//
-// This code is based on the code found from 7-Zip, which has a modified
-// version of the SHA-256 found from Crypto++ <https://www.cryptopp.com/>.
-// The code was modified a little to fit into liblzma.
+// The C code is based on the public domain SHA-256 code found from
+// Crypto++ Library 5.5.1 released in 2007: https://www.cryptopp.com/
+// A few minor tweaks have been made in liblzma.
//
-// Authors: Kevin Springle
-// Wei Dai
-// Igor Pavlov
+// Authors: Wei Dai
// Lasse Collin
//
-// This file has been put into the public domain.
-// You can do whatever you want with this file.
-//
///////////////////////////////////////////////////////////////////////////////
#include "check.h"
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-25 00:04:49 +0000