gcc-4.5.1 x86 naked patch (experimental)

diff -cr gcc.orig/gcc/config/i386/i386.c gcc/gcc/config/i386/i386.c
*** gcc.orig/gcc/config/i386/i386.c   Thu Jul 22 06:42:02 2010
--- gcc/gcc/config/i386/i386.c   Thu Aug 19 17:24:05 2010
***************
*** 4842,4847 ****
--- 4842,4855 ----
    return false;
  }

+ static bool
+ ix86_function_naked (const_tree fntype)
+ {
+   if (lookup_attribute ("naked", DECL_ATTRIBUTES (fntype)))
+     return true;
+   return false;
+ }
+
  static enum calling_abi
  ix86_function_abi (const_tree fndecl)
  {
***************
*** 8478,8483 ****
--- 8486,8494 ----
    struct ix86_frame frame;
    HOST_WIDE_INT allocate;
    int gen_frame_pointer = frame_pointer_needed;
+
+   if (ix86_function_naked (current_function_decl))
+     return ;

    ix86_finalize_stack_realign_flags ();

***************
*** 8978,8983 ****
--- 8989,8997 ----
    HOST_WIDE_INT offset, red_offset;
    struct machine_cfa_state cfa_state_save = *ix86_cfa_state;
    bool using_drap;
+
+   if (ix86_function_naked (current_function_decl))
+     return ;

    ix86_finalize_stack_realign_flags ();

***************
*** 26117,26122 ****
--- 26131,26152 ----
      return NULL_TREE;
  }

+ static tree
+ ix86_handle_naked_attribute (tree *node, tree name,
+                               tree args ATTRIBUTE_UNUSED,
+                               int flags ATTRIBUTE_UNUSED, bool *no_add_attrs)
+ {
+   if (TREE_CODE (*node) != FUNCTION_DECL)
+     {
+       warning (OPT_Wattributes, "%qE attribute only applies to functions",
+                name);
+       *no_add_attrs = true;
+       return NULL_TREE;
+     }
+
+     return NULL_TREE;
+ }
+
  static bool
  ix86_ms_bitfield_layout_p (const_tree record_type)
  {
***************
*** 28988,28993 ****
--- 29018,29024 ----
    { "sysv_abi", 0, 0, false, true, true, ix86_handle_abi_attribute },
    { "ms_hook_prologue", 0, 0, true, false, false, ix86_handle_fndecl_attribute },
    /* End element.  */
+   { "naked", 0, 0, true, false, false, ix86_handle_naked_attribute },
    { NULL,        0, 0, false, false, false, NULL }
  };

diff -cr gcc.orig/gcc/function.c gcc/gcc/function.c
*** gcc.orig/gcc/function.c   Fri Feb 26 15:58:57 2010
--- gcc/gcc/function.c   Thu Aug 19 17:11:26 2010
***************
*** 5212,5224 ****
        start_sequence ();
        epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
        seq = gen_epilogue ();
!       emit_jump_insn (seq);
!
!       /* Retain a map of the epilogue insns.  */
!       record_insns (seq, NULL, &epilogue_insn_hash);
!       set_insn_locators (seq, epilogue_locator);

!       seq = get_insns ();
        end_sequence ();

        insert_insn_on_edge (seq, e);
--- 5212,5228 ----
        start_sequence ();
        epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
        seq = gen_epilogue ();
!
!      if (seq)
!       {
!         emit_jump_insn (seq);

!         /* Retain a map of the epilogue insns.  */
!           record_insns (seq, NULL, &epilogue_insn_hash);
!         set_insn_locators (seq, epilogue_locator);
!       }
!
!      seq = get_insns ();
        end_sequence ();

        insert_insn_on_edge (seq, e);