sh.c (sh_expand_prologue): Let the second toggle_sz be optimized away.

* config/sh/sh.c (sh_expand_prologue): Let the second toggle_sz be
optimized away.

From-SVN: r38976

gcc/ChangeLog

 2001-01-13  Alexandre Oliva  <aoliva@redhat.com>
 
+	* config/sh/sh.c (sh_expand_prologue): Let the second toggle_sz be
+	optimized away.
+
 	* config/sh/sh.c (mova_p): Fix test for mova_const.
 
 2001-01-13  Neil Booth  <neil@daikokuya.demon.co.uk>

gcc/config/sh/sh.c

@@ -3969,7 +3969,16 @@ sh_expand_prologue ()
     emit_insn (gen_GOTaddr2picreg ());
 
   if (target_flags != save_flags)
-    emit_insn (gen_toggle_sz ());
+    {
+      rtx insn = emit_insn (gen_toggle_sz ());
+
+      /* If we're lucky, a mode switch in the function body will
+	 overwrite fpscr, turning this insn dead.  Tell flow this
+	 insn is ok to delete.  */
+      REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_MAYBE_DEAD,
+					    const0_rtx,
+					    REG_NOTES (insn));
+    }
 
   target_flags = save_flags;