cmake: pass "-msse4.2" to when building crc32c.cc if HAVE_SSE42

Summary:
it turns out that, with older GCC shipped from centos7, the SSE42
intrinsics are not available even with "target" specified. so we
need to pass "-msse42" for checking compiler's sse4.2 support and
for building crc32c.cc which uses sse4.2 intrinsics for crc32.

Signed-off-by: Kefu Chai <tchaikov@gmail.com>
Closes https://github.com/facebook/rocksdb/pull/2950

Differential Revision: D6032298

Pulled By: siying

fbshipit-source-id: 124c946321043661b3fb0a70b6cdf4c9c5126ab4
This commit is contained in:
Kefu Chai 2017-10-11 12:14:53 -07:00 committed by Facebook Github Bot
parent 38bbc879a5
commit 019aa7074c
2 changed files with 10 additions and 10 deletions

View File

@ -179,8 +179,10 @@ else()
endif()
endif()
set(CMAKE_REQUIRED_FLAGS ${CMAKE_CXX_FLAGS})
include(CheckCXXSourceCompiles)
if(NOT MSVC)
set(CMAKE_REQUIRED_FLAGS "-msse4.2")
endif()
CHECK_CXX_SOURCE_COMPILES("
#include <cstdint>
#include <nmmintrin.h>
@ -188,6 +190,7 @@ int main() {
volatile uint32_t x = _mm_crc32_u32(0, 0);
}
" HAVE_SSE42)
unset(CMAKE_REQUIRED_FLAGS)
if(HAVE_SSE42)
add_definitions(-DHAVE_SSE42)
elseif(FORCE_SSE42)
@ -556,6 +559,12 @@ set(SOURCES
utilities/write_batch_with_index/write_batch_with_index_internal.cc
$<TARGET_OBJECTS:build_version>)
if(HAVE_SSE42 AND NOT FORCE_SSE42)
set_source_files_properties(
util/crc32c.cc
PROPERTIES COMPILE_FLAGS "-msse4.2")
endif()
if(WIN32)
list(APPEND SOURCES
port/win/io_win.cc

View File

@ -336,15 +336,6 @@ static inline void Slow_CRC32(uint64_t* l, uint8_t const **p) {
table0_[c >> 24];
}
#if defined(HAVE_SSE42) && defined(__GNUC__)
#if defined(__clang__)
#if __has_cpp_attribute(gnu::target)
__attribute__ ((target ("sse4.2")))
#endif
#else // gcc supports this since 4.4
__attribute__ ((target ("sse4.2")))
#endif
#endif
static inline void Fast_CRC32(uint64_t* l, uint8_t const **p) {
#ifndef HAVE_SSE42
Slow_CRC32(l, p);