Added CPU automatic detection. It examines /proc/cpuinfo (if exists) and finds...

Added CPU automatic detection. It examines /proc/cpuinfo (if exists) and finds out flags for -mcpu and -march.
TODO is --with-cpu configure option to force some other processor type.
Problem is not big as any Intel 686+ CPU will use -mcpu=pentiumpro anyway. Exceptions are Athlons and 586 processors.

BUILD/SETUP.sh

@@ -40,7 +40,7 @@ c_warnings="$global_warnings -Wunused"
 cxx_warnings="$global_warnings -Woverloaded-virtual -Wextern-inline -Wsign-promo -Wreorder -Wctor-dtor-privacy -Wnon-virtual-dtor"
 
 alpha_cflags="-mcpu=ev6 -Wa,-mev6"	# Not used yet
-pentium_cflags="-mpentiumpro"
+pentium_cflags=""
 sparc_cflags=""
 
 # be as fast as we can be without losing our ability to backtrace

acinclude.m4

@@ -642,6 +642,53 @@ fi
 AC_MSG_RESULT($ac_cv_conv_longlong_to_float)
 ])
 
+AC_DEFUN(MYSQL_CHECK_CPU,
+AC_CACHE_CHECK([if compiler supports optimizations for current cpu], mysql_cv_cpu,[
+
+ac_save_CFLAGS="$CFLAGS"
+if test -r /proc/cpuinfo ; then
+  cpuinfo="cat /proc/cpuinfo"
+  cpu_family=`$cpuinfo | grep 'cpu family' | cut -d ':' -f 2 | cut -d ' ' -f 2 | head -1`
+  cpu_vendor=`$cpuinfo | grep 'vendor_id' | cut -d ':' -f 2 | cut -d ' ' -f 2 | head -1`
+fi 
+if test "$cpu_vendor" = "AuthenticAMD"; then
+    if test $cpu_family>=6; then
+      cpu_set="athlon pentiumpro k5 pentium i486 i386";
+    elif test $cpu_family=5; then
+      cpu_set="k5 pentium i486 i386";
+    elif test $cpu_family=4; then
+      cpu_set="i486 i386"
+    else
+      cpu_set="i386"
+    fi
+elif test "$cpu_vendor" = "GenuineIntel"; then
+    if test $cpu_family>=6; then
+      cpu_set=" pentiumpro pentium i486 i386";
+    elif test $cpu_family=5; then
+      cpu_set="pentium i486 i386";
+    elif test $cpu_family=4; then
+      cpu_set="i486 i386"
+    else
+      cpu_set="i386"
+    fi
+fi
+
+for ac_arg in $cpu_set;
+do
+  CFLAGS="$ac_save_CFLAGS -mcpu=$ac_arg -march=$ac_arg"
+  echo "trying $ac_arg";
+  AC_TRY_COMPILE([],[int i],mysql_cv_cpu=$ac_arg; break;, mysql_cv_cpu="unknown")
+done
+
+if test "$mysql_cv_cpu" = "unknown"
+then
+  CFLAGS="$ac_save_CFLAGS"
+      AC_MSG_RESULT(none)
+else
+      AC_MSG_RESULT($mysql_cv_cpu)
+fi
+]))
+
 AC_DEFUN(MYSQL_CHECK_VIO, [
   AC_ARG_WITH([vio],
               [\

configure.in

@@ -1673,6 +1673,7 @@ AC_ARG_WITH(embedded-server,
     [with_embedded_server=no]
 )
 
+MYSQL_CHECK_CPU
 MYSQL_CHECK_MYSQLFS
 MYSQL_CHECK_VIO
 MYSQL_CHECK_OPENSSL