[Qemu-devel] [v3 3/3] configure: add options to config avx2

[Liang Li <liang.z.li@intel.com>]

Add the '--enable-avx2' & '--disable-avx2' option so as to config
the AVX2 instruction optimization.

If '--disable-avx2' is not set, configure will detect if the compiler
can support AVX2 option, if yes, AVX2 optimization is eabled, else
disabled.

Signed-off-by: Liang Li <liang.z.li@intel.com>
---
 configure | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/configure b/configure
index 394db3b..94e45fa 100755
--- a/configure
+++ b/configure
@@ -311,6 +311,7 @@ libusb=""
 usb_redir=""
 opengl=""
 ifunc=""
+avx2=""
 zlib="yes"
 lzo=""
 snappy=""
@@ -1063,6 +1064,10 @@ for opt do
   ;;
   --enable-usb-redir) usb_redir="yes"
   ;;
+  --disable-avx2) avx2="no"
+  ;;
+  --enable-avx2) avx2="yes"
+  ;;
   --disable-zlib-test) zlib="no"
   ;;
   --disable-lzo) lzo="no"
@@ -1378,6 +1383,7 @@ disabled with --disable-FEATURE, default is enabled if available:
   smartcard       smartcard support (libcacard)
   libusb          libusb (for usb passthrough)
   usb-redir       usb network redirection support
+  avx2            support of avx2 instruction
   lzo             support of lzo compression library
   snappy          support of snappy compression library
   bzip2           support of bzip2 compression library
@@ -1841,6 +1847,23 @@ else
     ifunc="no"
 fi
 
+########################################
+# avx2 check
+
+if test "$avx2" != "no" ; then
+    cat > $TMPC << EOF
+int main(void) { return 0; }
+EOF
+    if compile_prog "" "-mavx2" ; then
+        avx2="yes"
+    else
+        if test "$avx2" = "yes" ; then
+            feature_not_found "avx2" "Your compiler don't support avx2"
+        fi
+        avx2="no"
+    fi
+fi
+
 #########################################
 # zlib check
 
@@ -4853,6 +4876,7 @@ echo "TPM passthrough   $tpm_passthrough"
 echo "QOM debugging     $qom_cast_debug"
 echo "vhdx              $vhdx"
 echo "ifunc support     $ifunc"
+echo "avx2 support      $avx2"
 echo "lzo support       $lzo"
 echo "snappy support    $snappy"
 echo "bzip2 support     $bzip2"
@@ -5241,6 +5265,12 @@ if test "$ifunc" = "yes" ; then
   echo "CONFIG_IFUNC=y" >> $config_host_mak
 fi
 
+if test "$avx2" = "yes" ; then
+  avx2_cflags=" -mavx2"
+  echo "AVX2_CFLAGS=$avx2_cflags" >> $config_host_mak
+  echo "CONFIG_AVX2=y" >> $config_host_mak
+fi
+
 if test "$lzo" = "yes" ; then
   echo "CONFIG_LZO=y" >> $config_host_mak
 fi
-- 
1.9.1