arm.c (arm_unwind_emit): Suppress unused unwinding annotations.

2008-03-15  Paul Brook  <paul@codesourcery.com>

	gcc/
	* config/arm/arm.c (arm_unwind_emit): Suppress unused unwinding
	annotations.
	(arm_output_fn_unwind): Mark functions that can not be unwound.

From-SVN: r133266

gcc/ChangeLog

 2008-03-15  Paul Brook  <paul@codesourcery.com>
 
+	* config/arm/arm.c (arm_unwind_emit): Suppress unused unwinding
+	annotations.
+	(arm_output_fn_unwind): Mark functions that can not be unwound.
+
+2008-03-15  Paul Brook  <paul@codesourcery.com>
+
 	* config/arm/arm.c (arm_rtx_costs_1): Add costs for ARMv6 value
 	extension instructions.
 

gcc/config/arm/arm.c

@@ -18633,6 +18633,11 @@ arm_unwind_emit (FILE * asm_out_file, rtx insn)
   if (!ARM_EABI_UNWIND_TABLES)
     return;
 
+  if (!(flag_unwind_tables || cfun->uses_eh_lsda)
+      && (TREE_NOTHROW (current_function_decl)
+	  || cfun->all_throwers_are_sibcalls))
+    return;
+
   if (GET_CODE (insn) == NOTE || !RTX_FRAME_RELATED_P (insn))
     return;
 
@@ -18713,7 +18718,17 @@ arm_output_fn_unwind (FILE * f, bool prologue)
   if (prologue)
     fputs ("\t.fnstart\n", f);
   else
-    fputs ("\t.fnend\n", f);
+    {
+      /* If this function will never be unwound, then mark it as such.
+         The came condition is used in arm_unwind_emit to suppress
+	 the frame annotations.  */
+      if (!(flag_unwind_tables || cfun->uses_eh_lsda)
+	  && (TREE_NOTHROW (current_function_decl)
+	      || cfun->all_throwers_are_sibcalls))
+	fputs("\t.cantunwind\n", f);
+
+      fputs ("\t.fnend\n", f);
+    }
 }
 
 static bool