From 90fa9e17bf3cafd95f2ad00d18a7c8c85be2b778 Mon Sep 17 00:00:00 2001
From: Richard Guenther <rguenther@suse.de>
Date: Fri, 2 Jul 2010 13:25:23 +0000
Subject: [PATCH] tree-ssa-structalias.c (pt_solution_set_var): New function.

2010-07-02  Richard Guenther  <rguenther@suse.de>

	* tree-ssa-structalias.c (pt_solution_set_var): New function.
	* tree-ssa-alias.h (pt_solution_set_var): Declare.
	* tree-ssa-loop-ivopts.c (copy_ref_info): Also copy or create
	points-to information.

From-SVN: r161716
---
 gcc/ChangeLog              |  7 +++++++
 gcc/tree-ssa-alias.h       |  2 ++
 gcc/tree-ssa-loop-ivopts.c | 21 +++++++++++++++++++++
 gcc/tree-ssa-structalias.c | 11 +++++++++++
 4 files changed, 41 insertions(+)

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a397936756c..63e9f3fe788 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2010-07-02  Richard Guenther  <rguenther@suse.de>
+
+	* tree-ssa-structalias.c (pt_solution_set_var): New function.
+	* tree-ssa-alias.h (pt_solution_set_var): Declare.
+	* tree-ssa-loop-ivopts.c (copy_ref_info): Also copy or create
+	points-to information.
+
 2010-07-02  Christian Borntraeger  <borntraeger@de.ibm.com>
 
 	* config/s390/s390.c (override_options): Adopt prefetching
diff --git a/gcc/tree-ssa-alias.h b/gcc/tree-ssa-alias.h
index a2b532747c6..499559d07e8 100644
--- a/gcc/tree-ssa-alias.h
+++ b/gcc/tree-ssa-alias.h
@@ -132,6 +132,8 @@ extern bool pt_solutions_same_restrict_base (struct pt_solution *,
 					     struct pt_solution *);
 extern void pt_solution_reset (struct pt_solution *);
 extern void pt_solution_set (struct pt_solution *, bitmap, bool, bool);
+extern void pt_solution_set_var (struct pt_solution *, tree);
+
 extern void dump_pta_stats (FILE *);
 
 extern GTY(()) struct pt_solution ipa_escaped_pt;
diff --git a/gcc/tree-ssa-loop-ivopts.c b/gcc/tree-ssa-loop-ivopts.c
index 46356588c94..02677fa9049 100644
--- a/gcc/tree-ssa-loop-ivopts.c
+++ b/gcc/tree-ssa-loop-ivopts.c
@@ -5549,6 +5549,27 @@ copy_ref_info (tree new_ref, tree old_ref)
       TMR_ORIGINAL (new_ref) = unshare_and_remove_ssa_names (old_ref);
       TREE_SIDE_EFFECTS (new_ref) = TREE_SIDE_EFFECTS (old_ref);
       TREE_THIS_VOLATILE (new_ref) = TREE_THIS_VOLATILE (old_ref);
+      /* We can transfer points-to information from an old pointer
+         or decl base to the new one.  */
+      if (TMR_BASE (new_ref)
+	  && TREE_CODE (TMR_BASE (new_ref)) == SSA_NAME
+	  && POINTER_TYPE_P (TREE_TYPE (TMR_BASE (new_ref)))
+	  && !SSA_NAME_PTR_INFO (TMR_BASE (new_ref)))
+	{
+	  tree base = get_base_address (old_ref);
+	  if ((INDIRECT_REF_P (base)
+	       || TREE_CODE (base) == MEM_REF)
+	      && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
+	    duplicate_ssa_name_ptr_info
+	      (TMR_BASE (new_ref), SSA_NAME_PTR_INFO (TREE_OPERAND (base, 0)));
+	  else if (TREE_CODE (base) == VAR_DECL
+		   || TREE_CODE (base) == PARM_DECL
+		   || TREE_CODE (base) == RESULT_DECL)
+	    {
+	      struct ptr_info_def *pi = get_ptr_info (TMR_BASE (new_ref));
+	      pt_solution_set_var (&pi->pt, base);
+	    }
+	}
     }
 }
 
diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index b0efcfa3473..5a84b58d5fd 100644
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -5817,6 +5817,17 @@ pt_solution_set (struct pt_solution *pt, bitmap vars,
   pt->vars_contains_restrict = vars_contains_restrict;
 }
 
+/* Set the points-to solution *PT to point only to the variable VAR.  */
+
+void
+pt_solution_set_var (struct pt_solution *pt, tree var)
+{
+  memset (pt, 0, sizeof (struct pt_solution));
+  pt->vars = BITMAP_GGC_ALLOC ();
+  bitmap_set_bit (pt->vars, DECL_UID (var));
+  pt->vars_contains_global = is_global_var (var);
+}
+
 /* Computes the union of the points-to solutions *DEST and *SRC and
    stores the result in *DEST.  This changes the points-to bitmap
    of *DEST and thus may not be used if that might be shared.