builtins.c (expand_builtin_mathfn, [...]): Avoid busy work when builtin is not…

builtins.c (expand_builtin_mathfn, [...]): Avoid busy work when builtin is not supported by the backend.

	* builtins.c (expand_builtin_mathfn, expand_builtin_mathfn_2): Avoid
	busy work when builtin is not supported by the backend.

From-SVN: r68681

gcc/ChangeLog

+Sun Jun 29 23:06:32 CEST 2003  Jan Hubicka  <jh@suse.cz>
+
+	* builtins.c (expand_builtin_mathfn, expand_builtin_mathfn_2): Avoid
+	busy work when builtin is not supported by the backend.
+
 2003-06-29  Zdenek Dvorak  <rakdver@atrey.karlin.mff.cuni.cz>
 
 	* loop.c (count_one_set): Fix detection of registers set in more

gcc/builtins.c

@@ -1789,6 +1789,10 @@ expand_builtin_mathfn (tree exp, rtx target, rtx subtarget)
 
   /* Make a suitable register to place result in.  */
   mode = TYPE_MODE (TREE_TYPE (exp));
+
+  /* Before working hard, check whether the instruction is available.  */
+  if (builtin_optab->handlers[(int) mode].insn_code == CODE_FOR_nothing)
+    return 0;
   target = gen_reg_rtx (mode);
 
   if (! flag_errno_math || ! HONOR_NANS (mode))
@@ -1874,6 +1878,11 @@ expand_builtin_mathfn_2 (tree exp, rtx target, rtx subtarget)
 
   /* Make a suitable register to place result in.  */
   mode = TYPE_MODE (TREE_TYPE (exp));
+
+  /* Before working hard, check whether the instruction is available.  */
+  if (builtin_optab->handlers[(int) mode].insn_code == CODE_FOR_nothing)
+    return 0;
+
   target = gen_reg_rtx (mode);
 
   if (! flag_errno_math || ! HONOR_NANS (mode))