* configure.in: Add AC_ARG_ENABLE for Haifa as documentation.

From-SVN: r16593

gcc/ChangeLog

+Thu Nov 20 00:38:46 1997  Dave Love  <d.love@dl.ac.uk>
+
+	* configure.in: Add AC_ARG_ENABLE for Haifa as documentation.
+
 Wed Nov 19 12:03:04 1997  Philippe De Muyter  <phdm@macqel.be>
 
 	* dwarf2out.c (CIE_LENGTH_LABEL, FDE_LENGTH_LABEL): New macros.

gcc/configure.in

@@ -85,6 +85,12 @@ if [[[ x$enable_c_cpplib != xno ]]]; then
   extra_c_objs="${extra_c_objs} cpplib.o cppexp.o cpphash.o cpperror.o"
   extra_c_flags=-DUSE_CPPLIB=1
 fi)
+  
+# Enable Haifa scheduler.
+AC_ARG_ENABLE(haifa,
+[  --enable-haifa          Use the experimental scheduler.
+  --disable-haifa         Don't use the experimental scheduler for the
+                          targets which normally enable it.])
 
 # Enable threads
 # Pass with no value to take the default

gcc/install.texi

@@ -176,6 +176,16 @@ point unit.  These systems include @samp{m68k-sun-sunos@var{n}} and
 effect, though perhaps there are other systems where it could usefully
 make a difference.
 
+@cindex Haifa scheduler
+@cindex scheduler, experimental
+@item --enable-haifa
+@item --disable-haifa
+Use @samp{--enable-haifa} to enable use of an experimental instruction
+scheduler (from IBM Haifa).  This may or may not produce better code.
+Some targets on which it is known to be a win enable it by default; use
+@samp{--disable-haifa} to disable it in these cases.  @code{configure}
+will print out whether the Haifa scheduler is enabled when it is run.
+
 @cindex Objective C threads
 @cindex threads, Objective C
 @item --enable-objcthreads=@var{type}