re PR target/54546 (SH: Enable -fshrink-wrap)

       PR target/54546
       * config/sh/sh-protos.h (sh_need_epilogue): Delete.
       (sh_can_use_simple_return_p): Declare.
       * config/sh/sh.c (sh_can_use_simple_return_p): Define.
       (sh_need_epilogue, sh_need_epilogue_known): Delete.
       (sh_output_function_epilogue): Remove sh_need_epilogue_known.
       * config/sh/sh.md (simple_return, return): Define.
       (epilogue): Use inline return rtl.
       (sh_expand_epilogue): Cleanup parameters boolean type.
       * config/sh/iterators.md (any_return): New iterator.

From-SVN: r191301

gcc/ChangeLog

 2012-09-14  Christian Bruel  <christian.bruel@st.com>
 
+	PR target/54546
+	* config/sh/sh-protos.h (sh_need_epilogue): Delete.
+	(sh_can_use_simple_return_p): Declare.
+	* config/sh/sh.c (sh_can_use_simple_return_p): Define.
+	(sh_need_epilogue, sh_need_epilogue_known): Delete.
+	(sh_output_function_epilogue): Remove sh_need_epilogue_known.
+	* config/sh/sh.md (simple_return, return): Define.
+	(epilogue): Use inline return rtl.
+	(sh_expand_epilogue): Cleanup parameters boolean type.
+	* config/sh/iterators.md (any_return): New iterator.
+
+2012-09-14  Christian Bruel  <christian.bruel@st.com>
+
 	* config/sh/predicates.md (t_reg_operand): Check REG_P for SUBREG.
 	* config/sh/sh.c (sequence_insn_p: Check INSNP_P for SEQUENCE.
 

gcc/config/sh/iterators.md

@@ -34,3 +34,6 @@
 (define_mode_attr disp04 [(QI "K04") (HI "K05")])
 (define_mode_attr disp12 [(QI "K12") (HI "K13")])
 
+;; Return codes.
+(define_code_iterator any_return [return simple_return])
+

gcc/config/sh/sh-protos.h

@@ -117,7 +117,6 @@ extern rtx get_fpscr_rtx (void);
 extern int sh_media_register_for_return (void);
 extern void sh_expand_prologue (void);
 extern void sh_expand_epilogue (bool);
-extern bool sh_need_epilogue (void);
 extern void sh_set_return_address (rtx, rtx);
 extern int initial_elimination_offset (int, int);
 extern bool fldi_ok (void);
@@ -155,4 +154,5 @@ extern int sh2a_get_function_vector_number (rtx);
 extern bool sh2a_is_function_vector_call (rtx);
 extern void sh_fix_range (const char *);
 extern bool sh_hard_regno_mode_ok (unsigned int, enum machine_mode);
+extern bool sh_can_use_simple_return_p (void);
 #endif /* ! GCC_SH_PROTOS_H */

gcc/config/sh/sh.c

@@ -7899,24 +7899,6 @@ sh_expand_epilogue (bool sibcall_p)
     emit_use (gen_rtx_REG (SImode, PR_REG));
 }
 
-static int sh_need_epilogue_known = 0;
-
-bool
-sh_need_epilogue (void)
-{
-  if (! sh_need_epilogue_known)
-    {
-      rtx epilogue;
-
-      start_sequence ();
-      sh_expand_epilogue (0);
-      epilogue = get_insns ();
-      end_sequence ();
-      sh_need_epilogue_known = (epilogue == NULL ? -1 : 1);
-    }
-  return sh_need_epilogue_known > 0;
-}
-
 /* Emit code to change the current function's return address to RA.
    TEMP is available as a scratch register, if needed.  */
 
@@ -7996,7 +7978,6 @@ static void
 sh_output_function_epilogue (FILE *file ATTRIBUTE_UNUSED,
 			     HOST_WIDE_INT size ATTRIBUTE_UNUSED)
 {
-  sh_need_epilogue_known = 0;
 }
 
 static rtx
@@ -12955,4 +12936,34 @@ sh_init_sync_libfuncs (void)
   init_sync_libfuncs (UNITS_PER_WORD);
 }
 
+/* Return true if it is appropriate to emit `ret' instructions in the
+   body of a function.  */
+
+bool
+sh_can_use_simple_return_p (void)
+{
+  HARD_REG_SET live_regs_mask;
+  int d;
+
+  if (! reload_completed || frame_pointer_needed)
+    return false;
+
+  /* Moving prologue around does't reduce the size.  */
+  if (optimize_function_for_size_p (cfun))
+    return false;
+
+  /* Can't optimize CROSSING_JUMPS for now.  */
+  if (flag_reorder_blocks_and_partition)
+    return false;
+
+  /* Finally, allow for pr save.  */
+  d = calc_live_regs (&live_regs_mask);
+
+  if (rounded_frame_size (d) > 4)
+   return false;
+
+  return true;
+
+}
+
 #include "gt-sh.h"

gcc/config/sh/sh.md

@@ -9335,7 +9335,7 @@ label:
   [(return)]
   ""
 {
-  sh_expand_epilogue (1);
+  sh_expand_epilogue (true);
   if (TARGET_SHCOMPACT)
     {
       rtx insn, set;
@@ -10154,9 +10154,13 @@ label:
 }
   [(set_attr "type" "load_media")])
 
+(define_expand "simple_return"
+  [(simple_return)]
+ "sh_can_use_simple_return_p ()")
+
 (define_expand "return"
   [(return)]
-  "reload_completed && ! sh_need_epilogue ()"
+ "reload_completed && epilogue_completed"
 {
   if (TARGET_SHMEDIA)
     {
@@ -10172,8 +10176,8 @@ label:
     }
 })
 
-(define_insn "*return_i"
-  [(return)]
+(define_insn "*<code>_i"
+  [(any_return)]
   "TARGET_SH1 && ! (TARGET_SHCOMPACT
 		    && (crtl->args.info.call_cookie
 			& CALL_COOKIE_RET_TRAMP (1)))
@@ -10299,19 +10303,12 @@ label:
 (define_expand "prologue"
   [(const_int 0)]
   ""
-{
-  sh_expand_prologue ();
-  DONE;
-})
+  "sh_expand_prologue (); DONE;")
 
 (define_expand "epilogue"
   [(return)]
   ""
-{
-  sh_expand_epilogue (0);
-  emit_jump_insn (gen_return ());
-  DONE;
-})
+  "sh_expand_epilogue (false);")
 
 (define_expand "eh_return"
   [(use (match_operand 0 "register_operand" ""))]