build: verify that the assembler can handle crc32 functions

Also, enable crc32 even if -msse4.2 wasn't added by us, as long as it works.
This allows custom flags (such as -march=native) to work as expected.
This commit is contained in:
Cory Fields 2017-07-12 12:58:20 -04:00
parent e8b95239ee
commit d34d77a51b
2 changed files with 26 additions and 3 deletions

View File

@ -246,9 +246,32 @@ if test "x$CXXFLAGS_overridden" = "xno"; then
# Check for optional instruction set support. Enabling these does _not_ imply that all code will
# be compiled with them, rather that specific objects/libs may use them after checking for runtime
# compatibility.
AX_CHECK_COMPILE_FLAG([-msse4.2],[[enable_sse42=yes; SSE42_CXXFLAGS="-msse4.2"]],,[[$CXXFLAG_WERROR]])
AX_CHECK_COMPILE_FLAG([-msse4.2],[[SSE42_CXXFLAGS="-msse4.2"]],,[[$CXXFLAG_WERROR]])
fi
TEMP_CXXFLAGS="$CXXFLAGS"
CXXFLAGS="$CXXFLAGS $SSE42_CXXFLAGS"
AC_MSG_CHECKING(for assembler crc32 support)
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
#include <stdint.h>
#if defined(_MSC_VER)
#include <intrin.h>
#elif defined(__GNUC__) && defined(__SSE4_2__)
#include <nmmintrin.h>
#endif
]],[[
uint64_t l = 0;
l = _mm_crc32_u8(l, 0);
l = _mm_crc32_u32(l, 0);
l = _mm_crc32_u64(l, 0);
return l;
]])],
[ AC_MSG_RESULT(yes); enable_hwcrc32=yes],
[ AC_MSG_RESULT(no)]
)
CXXFLAGS="$TEMP_CXXFLAGS"
CPPFLAGS="$CPPFLAGS -DHAVE_BUILD_INFO -D__STDC_FORMAT_MACROS"
AC_ARG_WITH([utils],
@ -1132,7 +1155,7 @@ AM_CONDITIONAL([USE_QRCODE], [test x$use_qr = xyes])
AM_CONDITIONAL([USE_LCOV],[test x$use_lcov = xyes])
AM_CONDITIONAL([GLIBC_BACK_COMPAT],[test x$use_glibc_compat = xyes])
AM_CONDITIONAL([HARDEN],[test x$use_hardening = xyes])
AM_CONDITIONAL([ENABLE_SSE42],[test x$enable_sse42 = xyes])
AM_CONDITIONAL([ENABLE_HWCRC32],[test x$enable_hwcrc32 = xyes])
AC_DEFINE(CLIENT_VERSION_MAJOR, _CLIENT_VERSION_MAJOR, [Major version])
AC_DEFINE(CLIENT_VERSION_MINOR, _CLIENT_VERSION_MINOR, [Minor version])

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@ -142,7 +142,7 @@ leveldb_libmemenv_a_SOURCES += leveldb/helpers/memenv/memenv.h
leveldb_libleveldb_sse42_a_CPPFLAGS = $(leveldb_libleveldb_a_CPPFLAGS)
leveldb_libleveldb_sse42_a_CXXFLAGS = $(leveldb_libleveldb_a_CXXFLAGS)
if ENABLE_SSE42
if ENABLE_HWCRC32
leveldb_libleveldb_sse42_a_CPPFLAGS += -DLEVELDB_PLATFORM_POSIX_SSE
leveldb_libleveldb_sse42_a_CXXFLAGS += $(SSE42_CXXFLAGS)
endif