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[patch] m68k: Correctly emit a return insn.


Hi,

Attached is a patch to correctly emit a return insn.

I've noticed that

  void foo (void) {}

is compiled into

foo:
        link.w %fp,#0
        unlk %fp

with -O2 without "rts" at the end.

This is because the RTL DCE pass thinks that the "(return)" insn is
unused because the insn is mistakenly a NONJUMP_INSN.  This patch
fixes the problem by emitting the "(return)" insn as a JUMP_INSN.

Tested by running "Hello, world".  Committed as obvious.

Kazu Hirata

2007-06-18  Kazu Hirata  <kazu@codesourcery.com>

	* config/m68k/m68k.c (m68k_expand_epilogue): Emit a return
	insn with emit_jump_insn.

Index: gcc/config/m68k/m68k.c
===================================================================
--- gcc/config/m68k/m68k.c	(revision 125788)
+++ gcc/config/m68k/m68k.c	(working copy)
@@ -1214,7 +1214,7 @@ m68k_expand_epilogue (bool sibcall_p)
 			   EH_RETURN_STACKADJ_RTX));
 
   if (!sibcall_p)
-    emit_insn (gen_rtx_RETURN (VOIDmode));
+    emit_jump_insn (gen_rtx_RETURN (VOIDmode));
 }
 
 /* Return true if X is a valid comparison operator for the dbcc 


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