Fix PR50260

[Michael Matz <matz at suse dot de>]

Hi,

the last change in ipa-split generated a new use of a previously unused 
PARM_DECL.  When one does this one has to call add_referenced_var.  Not 
doing so can cause segfault when accessing the (not initialized) var 
annotation.  So, fixed with the patch.

I took the opportunity to remove all explicit calls to get_var_ann because 
add_referenced_var is doing so as first thing.  Reviewing the code showed 
one potentially problematic case in tree-ssa-pre.c where a new variable 
was created without calling add_referenced_var.  It's only for 
place-holder SSA names but those can conceivably leak into the program 
stream by being reused during expression generation.

Currently regstrapping on x86_64-linux (without Ada).  Okay for trunk?


Ciao,
Michael.
-- 
	PR middle-end/50260
	* ipa-split.c (split_function): Call add_referenced_var.

	* tree-ssa-phiopt.c (cond_store_replacement): Don't call get_var_ann.
	(cond_if_else_store_replacement_1): Ditto.
	* tree-ssa-pre.c (get_representative_for): Ditto.
	(create_expression_by_pieces): Ditto.
	(insert_into_preds_of_block): Ditto.
	* tree-sra.c (create_access_replacement): Ditto.
	(get_replaced_param_substitute): Ditto.

testsuite/
	* gfortran.fortran-torture/compile/pr50260.f90: New test.

Index: ipa-split.c
===================================================================
--- ipa-split.c	(revision 178408)
+++ ipa-split.c	(working copy)
@@ -988,6 +988,9 @@ split_function (struct split_point *spli
 	arg = gimple_default_def (cfun, parm);
 	if (!arg)
 	  {
+	    /* This parm wasn't used up to now, but is going to be used,
+	       hence register it.  */
+	    add_referenced_var (parm);
 	    arg = make_ssa_name (parm, gimple_build_nop ());
 	    set_default_def (parm, arg);
 	  }
Index: tree-ssa-phiopt.c
===================================================================
--- tree-ssa-phiopt.c	(revision 178408)
+++ tree-ssa-phiopt.c	(working copy)
@@ -1269,10 +1269,7 @@ cond_store_replacement (basic_block midd
   /* 2) Create a temporary where we can store the old content
         of the memory touched by the store, if we need to.  */
   if (!condstoretemp || TREE_TYPE (lhs) != TREE_TYPE (condstoretemp))
-    {
-      condstoretemp = create_tmp_reg (TREE_TYPE (lhs), "cstore");
-      get_var_ann (condstoretemp);
-    }
+    condstoretemp = create_tmp_reg (TREE_TYPE (lhs), "cstore");
   add_referenced_var (condstoretemp);
 
   /* 3) Insert a load from the memory of the store to the temporary
@@ -1355,10 +1352,7 @@ cond_if_else_store_replacement_1 (basic_
   /* 2) Create a temporary where we can store the old content
 	of the memory touched by the store, if we need to.  */
   if (!condstoretemp || TREE_TYPE (lhs) != TREE_TYPE (condstoretemp))
-    {
-      condstoretemp = create_tmp_reg (TREE_TYPE (lhs), "cstore");
-      get_var_ann (condstoretemp);
-    }
+    condstoretemp = create_tmp_reg (TREE_TYPE (lhs), "cstore");
   add_referenced_var (condstoretemp);
 
   /* 3) Create a PHI node at the join block, with one argument
Index: tree-ssa-pre.c
===================================================================
--- tree-ssa-pre.c	(revision 178408)
+++ tree-ssa-pre.c	(working copy)
@@ -1399,7 +1399,7 @@ get_representative_for (const pre_expr e
   if (!pretemp || exprtype != TREE_TYPE (pretemp))
     {
       pretemp = create_tmp_reg (exprtype, "pretmp");
-      get_var_ann (pretemp);
+      add_referenced_var (pretemp);
     }
 
   name = make_ssa_name (pretemp, gimple_build_nop ());
@@ -3178,10 +3178,7 @@ create_expression_by_pieces (basic_block
   /* Build and insert the assignment of the end result to the temporary
      that we will return.  */
   if (!pretemp || exprtype != TREE_TYPE (pretemp))
-    {
-      pretemp = create_tmp_reg (exprtype, "pretmp");
-      get_var_ann (pretemp);
-    }
+    pretemp = create_tmp_reg (exprtype, "pretmp");
 
   temp = pretemp;
   add_referenced_var (temp);
@@ -3441,10 +3438,7 @@ insert_into_preds_of_block (basic_block
 
   /* Now build a phi for the new variable.  */
   if (!prephitemp || TREE_TYPE (prephitemp) != type)
-    {
-      prephitemp = create_tmp_var (type, "prephitmp");
-      get_var_ann (prephitemp);
-    }
+    prephitemp = create_tmp_var (type, "prephitmp");
 
   temp = prephitemp;
   add_referenced_var (temp);
Index: tree-sra.c
===================================================================
--- tree-sra.c	(revision 178408)
+++ tree-sra.c	(working copy)
@@ -1825,7 +1825,6 @@ create_access_replacement (struct access
   tree repl;
 
   repl = create_tmp_var (access->type, "SR");
-  get_var_ann (repl);
   add_referenced_var (repl);
   if (rename)
     mark_sym_for_renaming (repl);
@@ -4106,7 +4105,6 @@ get_replaced_param_substitute (struct ip
       DECL_NAME (repl) = get_identifier (pretty_name);
       obstack_free (&name_obstack, pretty_name);
 
-      get_var_ann (repl);
       add_referenced_var (repl);
       adj->new_ssa_base = repl;
     }
Index: testsuite/gfortran.fortran-torture/compile/pr50260.f90
===================================================================
--- testsuite/gfortran.fortran-torture/compile/pr50260.f90	(revision 0)
+++ testsuite/gfortran.fortran-torture/compile/pr50260.f90	(revision 0)
@@ -0,0 +1,48 @@
+MODULE cp_parser_methods
+  INTEGER, PARAMETER :: default_string_length=80
+  INTEGER, PARAMETER :: default_path_length=250
+  TYPE ilist_type
+     LOGICAL                              :: in_use
+  END TYPE ilist_type
+  TYPE cp_parser_type
+     CHARACTER(LEN=default_path_length)             :: ifn
+     INTEGER                                        :: icol,icol1,icol2
+     TYPE(ilist_type), POINTER                      :: ilist
+  END TYPE cp_parser_type
+  TYPE cp_error_type
+  END TYPE cp_error_type
+CONTAINS
+  FUNCTION cts(i) RESULT(res)
+    CHARACTER(len=6)                         :: res
+  END FUNCTION cts
+  FUNCTION parser_location(parser,error) RESULT(res)
+    TYPE(cp_parser_type), POINTER            :: parser
+    TYPE(cp_error_type), INTENT(inout)       :: error
+    CHARACTER(len=default_path_length+default_string_length)       :: res
+    LOGICAL                                  :: failure
+    IF (.NOT. failure) THEN
+       res="file:'"//TRIM(parser%ifn)//"' line:"//cts(parser%icol)
+    END IF
+  END FUNCTION parser_location
+  SUBROUTINE parser_get_integer(parser,at_end, error)
+    TYPE(cp_parser_type), POINTER            :: parser
+    TYPE(cp_error_type), INTENT(inout)       :: error
+    LOGICAL                                  :: failure, my_at_end
+    IF (.NOT.failure) THEN
+       IF (.NOT.parser%ilist%in_use) THEN
+          CALL cp_assert("A"// TRIM(parser_location(parser,error)))
+       END IF
+    END IF
+  END SUBROUTINE parser_get_integer
+  SUBROUTINE parser_get_string(parser,at_end,error)
+    TYPE(cp_parser_type), POINTER            :: parser
+    LOGICAL, INTENT(out), OPTIONAL           :: at_end
+    TYPE(cp_error_type), INTENT(inout)       :: error
+    LOGICAL                                  :: failure, my_at_end
+    IF (.NOT.failure) THEN
+       IF (PRESENT(at_end)) THEN
+          CALL cp_assert("s"//TRIM(parser_location(parser,error)))
+       END IF
+    END IF
+  END SUBROUTINE parser_get_string
+END MODULE cp_parser_methods