i386.c (ix86_compute_frame_layout): Avoid stack-alignment for simple leaf-functions.

2010-06-21  Kai Tietz  <kai.tietz@onevision.com>

        * config/i386/i386.c (ix86_compute_frame_layout): Avoid
        stack-alignment for simple leaf-functions.

From-SVN: r161064

gcc/ChangeLog

+2010-06-21  Kai Tietz  <kai.tietz@onevision.com>
+
+	* config/i386/i386.c (ix86_compute_frame_layout): Avoid
+	stack-alignment for simple leaf-functions.
+
 2010-06-20  Alexandre Oliva  <aoliva@redhat.com>
 
 	* doc/install.texi: Document bootstrap-lto.

gcc/config/i386/i386.c

@@ -8101,8 +8101,10 @@ ix86_compute_frame_layout (struct ix86_frame *frame)
   preferred_alignment = crtl->preferred_stack_boundary / BITS_PER_UNIT;
 
   /* MS ABI seem to require stack alignment to be always 16 except for function
-     prologues.  */
-  if (ix86_cfun_abi () == MS_ABI && preferred_alignment < 16)
+     prologues and leaf.  */
+  if ((ix86_cfun_abi () == MS_ABI && preferred_alignment < 16)
+      && (!current_function_is_leaf || cfun->calls_alloca != 0
+          || ix86_current_function_calls_tls_descriptor))
     {
       preferred_alignment = 16;
       stack_alignment_needed = 16;