1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
###############################################################################
# Check for the presence of AVX and figure out the flags to use for it.
function(PCL_CHECK_FOR_AVX)
set(AVX_FLAGS)
include(CheckCXXSourceRuns)
if(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_GNUCXX OR CMAKE_COMPILER_IS_CLANG)
# Setting -march & -mtune just as required flags for check_cxx_source_runs,
# and CMAKE_REQUIRED_FLAGS will be restored after test runs.
set(CMAKE_REQUIRED_FLAGS "-march=native -mtune=native")
endif()
check_cxx_source_runs("
#include <immintrin.h>
int main()
{
__m256i a = {0};
a = _mm256_abs_epi16(a);
return 0;
}"
HAVE_AVX2)
if(NOT HAVE_AVX2)
check_cxx_source_runs("
#include <immintrin.h>
int main()
{
__m256 a;
a = _mm256_set1_ps(0);
return 0;
}"
HAVE_AVX)
endif()
set(CMAKE_REQUIRED_FLAGS)
# Setting the -mavx/-mavx2 defines __AVX(2)__, see here https://stackoverflow.com/a/28939692
# and this allows the compiler to use the codes for AVX behind code guards.
if(CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_GNUCXX OR CMAKE_COMPILER_IS_CLANG)
if(HAVE_AVX2)
set(AVX_FLAGS "-mavx2" PARENT_SCOPE)
elseif(HAVE_AVX)
set(AVX_FLAGS "-mavx" PARENT_SCOPE)
endif()
endif()
# Setting the /arch defines __AVX(2)__, see here https://docs.microsoft.com/en-us/cpp/build/reference/arch-x64?view=msvc-160
# AVX2 extends and includes AVX.
# Setting these defines allows the compiler to use AVX instructions as well as code guarded with the defines.
# TODO: Add AVX512 variant if needed.
if(MSVC)
if(HAVE_AVX2)
set(AVX_FLAGS "/arch:AVX2" PARENT_SCOPE)
elseif(HAVE_AVX)
set(AVX_FLAGS "/arch:AVX" PARENT_SCOPE)
endif()
endif()
endfunction()
|
