re PR middle-end/20548 (ACATS c52103x c52104x c52104y segfault)

	PR ada/20548
	* common.opt (-fstack-check): Do not declare the variable here.
	(-fstack-check=): New option variant.
	* doc/invoke.texi (Code Gen Options): Document it.
	* expr.h (STACK_OLD_CHECK_PROTECT): New macro.
	(STACK_CHECK_PROTECT): Bump to 3 pages if DWARF-2 EH is used.
	(STACK_CHECK_STATIC_BUILTIN): New macro.
	* doc/tm.texi (Stack Checking): Document STACK_CHECK_STATIC_BUILTIN.
	* opts.c: Include expr.h.
	(common_handle_option) <OPT_fold_stack_check_>: New case.
	<OPT_fstack_check>: Likewise.
	* calls.c (initialize_argument_information): Use TYPE_SIZE_UNIT
	consistently in the test for variable-sized types.  Adjust for
	new behaviour of flag_stack_check.
	* explow.c: Include except.h.
	(allocate_dynamic_stack_space): Do not take into account
	STACK_CHECK_MAX_FRAME_SIZE for static builtin stack checking.
	* function.c (gimplify_parameters): Use DECL_SIZE_UNIT in the test
	for variable-sized parameters.  Treat all parameters whose size is
	greater than STACK_CHECK_MAX_VAR_SIZE as variable-sized if generic
	stack checking is enabled.
	* gimplify.c (gimplify_decl_expr): Treat non-static objects whose
	size is greater than STACK_CHECK_MAX_VAR_SIZE as variable-sized
	if generic stack checking is enabled.
	(expand_function_end): Adjust for new behaviour of flag_stack_check.
	* reload1.c (reload): Likewise.
	* stmt.c (expand_decl): Assert that all automatic variables have
	fixed size at this point and remove dead code.
	* flags.h (stack_check_type): New enumeration type.
	(flag_stack_check): Declare.
	* toplev.c (flag_stack_check): New global variable.
	* Makefile.in (opts.o): Add dependency on EXPR_H.
	(explow.o): Add dependency on except.h.
ada/
	* gcc-interface/decl.c (gnat_to_gnu_entity): Use DECL_SIZE_UNIT in the
	setjmp test consistently.  Adjust for new behaviour of flag_stack_check.
	* gcc-interface/utils2.c (build_call_alloc_dealloc): Remove redundant
	test of flag_stack_check.  Adjust for new behaviour of flag_stack_check.

From-SVN: r139159

1 files changed, 9 insertions, 6 deletions

diff --git a/gcc/function.c b/gcc/function.c
index 98b8da07365..da26dc7d114 100644
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -3236,7 +3236,7 @@ gimplify_parameters (void)
       walk_tree_without_duplicates (&data.passed_type,
 				    gimplify_parm_type, &stmts);
 
-      if (!TREE_CONSTANT (DECL_SIZE (parm)))
+      if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
 	{
 	  gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
 	  gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
@@ -3250,9 +3250,12 @@ gimplify_parameters (void)
 	    {
 	      tree local, t;
 
-	      /* For constant sized objects, this is trivial; for
+	      /* For constant-sized objects, this is trivial; for
 		 variable-sized objects, we have to play games.  */
-	      if (TREE_CONSTANT (DECL_SIZE (parm)))
+	      if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
+		  && !(flag_stack_check == GENERIC_STACK_CHECK
+		       && compare_tree_int (DECL_SIZE_UNIT (parm),
+					    STACK_CHECK_MAX_VAR_SIZE) > 0))
 		{
 		  local = create_tmp_var (type, get_name (parm));
 		  DECL_IGNORED_P (local) = 0;
@@ -4480,10 +4483,10 @@ expand_function_end (void)
   if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
     get_arg_pointer_save_area ();
 
-  /* If we are doing stack checking and this function makes calls,
+  /* If we are doing generic stack checking and this function makes calls,
      do a stack probe at the start of the function to ensure we have enough
      space for another stack frame.  */
-  if (flag_stack_check && ! STACK_CHECK_BUILTIN)
+  if (flag_stack_check == GENERIC_STACK_CHECK)
     {
       rtx insn, seq;
 
@@ -4491,7 +4494,7 @@ expand_function_end (void)
 	if (CALL_P (insn))
 	  {
 	    start_sequence ();
-	    probe_stack_range (STACK_CHECK_PROTECT,
+	    probe_stack_range (STACK_OLD_CHECK_PROTECT,
 			       GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
 	    seq = get_insns ();
 	    end_sequence ();