configure.in support for FreeBSD ia64/sparc64/powerpc

[Giorgos Keramidas]

The following change makes Emacs buildable on FreeBSD running on
sparc64, ia64 and powerpc too.  It has been tested for some time as a
local patch in the editors/emacs-devel port of FreeBSD, so it would be
nice if it became part of Emacs 22.  We won't have to maintain local
diffs for this part then:

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diff -r e9c18eba38ea -r 355e6a7d786b configure.in
--- a/configure.in      Fri Oct 27 15:45:51 2006 +0000
+++ b/configure.in      Sat Oct 28 01:49:45 2006 +0300
@@ -237,6 +237,9 @@ case "${canonical}" in
     opsys=freebsd
     case "${canonical}" in
       alpha*-*-freebsd*)       machine=alpha ;;
+      ia64-*-freebsd*)         machine=ia64 ;;
+      sparc64-*-freebsd*)      machine=sparc ;;
+      powerpc-*-freebsd*)      machine=macppc ;;
       i[3456]86-*-freebsd*)    machine=intel386 ;;
       amd64-*-freebsd*|x86_64-*-freebsd*) machine=amdx86-64 ;;
     esac
diff -r e9c18eba38ea -r 355e6a7d786b src/alloc.c
--- a/src/alloc.c       Fri Oct 27 15:45:51 2006 +0000
+++ b/src/alloc.c       Sat Oct 28 01:49:45 2006 +0300
@@ -4560,7 +4560,11 @@ mark_stack ()
      needed on ia64 too.  See mach_dep.c, where it also says inline
      assembler doesn't work with relevant proprietary compilers.  */
 #ifdef sparc
+#ifdef __sparc64__
+  asm ("flushw");
+#else
   asm ("ta 3");
+#endif
 #endif
 
   /* Save registers that we need to see on the stack.  We need to see
%%%