Added a new configuration option, --enable-build-architecture, for

selecting the build architecture.
    configure.in:   Add the configuration option.
    INSTALL:        Documented it.
    chores.3dfx:    Make it selectable easily from this script.

glide3x/INSTALL

@@ -75,6 +75,9 @@ However, there are some small wrinkles.
                                   library to use.  The default value,
                                   texus, is the only one which is
                                   currently functional.
+      --enable-build-architecture Choose which architecture to build
+                                  for.  The legal values are i[3456]86,
+                                  or the alpha.
 4.) There is a script, build.3dfx, which is installed by the
     configure script at the root of every build directory.  It
     is essentially the single line:

glide3x/chores.3dfx

@@ -73,6 +73,10 @@ while [ ! -z "$1" ] && [ "$DONE" != YES ] ; do
         echo '    --texus2             Add configuration option to use'
         echo '                         the texus2 library.  (Do not use this'
         echo '                         unless you know what you are doing.)'
+        echo '    --architecture=arch  Configure for the given architecture.'
+        echo '                         Equivalent to giving'
+        echo '                             --enable-build-architecture=arch'
+        echo '                         to "configure".'
         echo '    --generate:          Generate configure script and'
         echo '                         makefile.autoconf.in files.'
         echo '                         This is essentially just:'
@@ -112,6 +116,10 @@ while [ ! -z "$1" ] && [ "$DONE" != YES ] ; do
         DO_GENERATE=YES
         shift
         ;;
+    --arch*=*)
+        CONFIGURE_OPTIONS="$CONFIGURE_OPTIONS --enable-build-architecture=`echo $1 | sed s/--arch[^=]*=//`"
+        shift
+        ;;
     --configure)
         DO_CONFIGURE=YES
         shift

glide3x/configure.in

@@ -137,6 +137,21 @@ AM_CONDITIONAL(FX_GLIDE_H3,  test x$FX_GLIDE_HW = xh3)
 AM_CONDITIONAL(FX_GLIDE_H5,  test x$FX_GLIDE_HW = xh5)
 AM_CONDITIONAL(FX_GLIDE_CVG, test x$FX_GLIDE_HW = xcvg)
 #
+# Architecture
+#
+AC_ARG_ENABLE([build-architecture],
+              [dnl
+  --enable-build-architecture Enable AMD 3DNow instructions [default=current]],
+              [case ${enableval} in
+               i[3456]86|alpha)
+                   FX_GLIDE_BUILD_ARCHITECTURE=${enableval}
+                   ;;
+               *)
+                   AC_MSG_ERROR([Illegal value (${enableval}) for --enable-build-architecture])
+                   ;;
+               esac],[enable_build_architecture=`uname -m`])
+AC_SUBST(FX_GLIDE_BUILD_ARCHITECTURE)
+#
 # Various tests needed at points in the build
 # First, we set defaults.
 #