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CMake: Add support for ARM64 CRC32 instruction detection.

This commit is contained in:
Jia Tan 2024-01-22 00:42:28 +08:00
parent c5f6d79cc9
commit 61908e8160

View file

@ -1007,6 +1007,56 @@ calculation if supported by the system" ON)
endif()
endif()
# ARM64 C Language Extensions define CRC32 functions in arm_acle.h.
# These are supported by at least GCC and Clang which both need
# __attribute__((__target__("+crc"))), unless the needed compiler flags
# are used to support the CRC instruction.
option(ALLOW_ARM64_CRC32 "Allow ARM64 CRC32 instruction if supported by \
the system" ON)
if(ALLOW_ARM64_CRC32)
check_c_source_compiles("
#include <stdint.h>
#ifndef _MSC_VER
#include <arm_acle.h>
#endif
#if (defined(__GNUC__) || defined(__clang__)) && !defined(__EDG__)
__attribute__((__target__(\"+crc\")))
#endif
uint32_t my_crc(uint32_t a, uint64_t b)
{
return __crc32d(a, b);
}
int main(void) { return 0; }
"
HAVE_ARM64_CRC32)
if(HAVE_ARM64_CRC32)
target_compile_definitions(liblzma PRIVATE HAVE_ARM64_CRC32)
# Check for ARM64 CRC32 instruction runtime detection.
# getauxval() is supported on Linux.
check_symbol_exists(getauxval sys/auxv.h HAVE_GETAUXVAL)
tuklib_add_definition_if(liblzma HAVE_GETAUXVAL)
# elf_aux_info() is supported on FreeBSD.
check_symbol_exists(elf_aux_info sys/auxv.h HAVE_ELF_AUX_INFO)
tuklib_add_definition_if(liblzma HAVE_ELF_AUX_INFO)
# sysctlbyname("hw.optional.armv8_crc32", ...) is supported on Darwin
# (macOS, iOS, etc.). Note that sysctlbyname() is supported on FreeBSD,
# NetBSD, and possibly others too but the string is specific to
# Apple OSes. The C code is responsible for checking
# defined(__APPLE__) before using
# sysctlbyname("hw.optional.armv8_crc32", ...).
check_symbol_exists(sysctlbyname sys/sysctl.h HAVE_SYSCTLBYNAME)
tuklib_add_definition_if(liblzma HAVE_SYSCTLBYNAME)
endif()
endif()
# Support -fvisiblity=hidden when building shared liblzma.
# These lines do nothing on Windows (even under Cygwin).
# HAVE_VISIBILITY should always be defined to 0 or 1.