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Diffstat (limited to 'src/liblzma/check/crc_common.h')
| -rw-r--r-- | src/liblzma/check/crc_common.h | 137 |
1 files changed, 137 insertions, 0 deletions
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 |