diff options
Diffstat (limited to 'configure.ac')
| -rw-r--r-- | configure.ac | 31 |
1 files changed, 18 insertions, 13 deletions
diff --git a/configure.ac b/configure.ac index 8a922cdcee4d..b37328188e38 100644 --- a/configure.ac +++ b/configure.ac @@ -7692,22 +7692,27 @@ if test "$GCC" = "yes" -o "$COM_IS_CLANG" = TRUE; then flag_f16c=-mf16c flag_fma=-mfma else - # https://docs.microsoft.com/en-us/cpp/build/reference/arch-x86 - # MSVC seems to differentiate only between SSE and SSE2, where in fact - # SSE2 seems to be SSE2+. - # Even if -arch:SSE2 is the default, set it explicitly, so that the variable - # is not empty (and can be tested in gbuild). - flag_sse2=-arch:SSE2 - flag_ssse3=-arch:SSE2 - flag_sse41=-arch:SSE2 - flag_sse42=-arch:SSE2 + # With MSVC using -arch is in fact not necessary for being able + # to use CPU intrinsics, code using AVX512F intrinsics will compile + # even if compiled with -arch:AVX, the -arch option really only affects + # instructions generated for C/C++ code. + # So use the matching same (or lower) -arch options, but only in order + # to generate the best matching instructions for the C++ code surrounding + # the intrinsics. + # SSE2 is the default for x86/x64, so no need to specify the option. + flag_sse2= + # No specific options for these, use the next lower. + flag_ssse3="$flag_sse2" + flag_sse41="$flag_sse2" + flag_sse42="$flag_sse2" flag_avx=-arch:AVX flag_avx2=-arch:AVX2 flag_avx512=-arch:AVX512 - flag_avx512f=-arch:AVX512 - # These are part of -arch:AVX2 - flag_f16c=-arch:AVX2 - flag_fma=-arch:AVX2 + # Using -arch:AVX512 would enable more than just AVX512F, so use only AVX2. + flag_avx512f=-arch:AVX2 + # No MSVC options for these. + flag_f16c="$flag_sse2" + flag_fma="$flag_sse2" fi AC_MSG_CHECKING([whether $CXX can compile SSE2 intrinsics]) |