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diff --git a/gcc/value-pointer-equiv.h b/gcc/value-pointer-equiv.h
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+/* Header file for the context-aware pointer equivalence tracker.
+   Copyright (C) 2020-2021 Free Software Foundation, Inc.
+   Contributed by Aldy Hernandez <aldyh@redhat.com>
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#ifndef GCC_VALUE_POINTER_EQUIV_H
+#define GCC_VALUE_POINTER_EQUIV_H
+
+// Simple context-aware pointer equivalency analyzer that returns what
+// a pointer SSA name is equivalent to at a given point during a walk
+// of the IL.
+//
+// Note that global equivalency take priority over conditional
+// equivalency.  That is, p = &q takes priority over a later p == &t.
+//
+// This class is meant to be called during a DOM walk.
+
+class pointer_equiv_analyzer
+{
+public:
+  pointer_equiv_analyzer (gimple_ranger *r);
+  ~pointer_equiv_analyzer ();
+  void enter (basic_block);
+  void leave (basic_block);
+  void visit_stmt (gimple *stmt);
+  tree get_equiv (tree ssa) const;
+
+private:
+  void visit_edge (edge e);
+  tree get_equiv_expr (tree_code code, tree expr) const;
+  void set_global_equiv (tree ssa, tree pointee);
+  void set_cond_equiv (tree ssa, tree pointee);
+
+  gimple_ranger *m_ranger;
+  // Global pointer equivalency indexed by SSA_NAME_VERSION.
+  tree *m_global_points;
+  // Conditional pointer equivalency.
+  class ssa_equiv_stack *m_cond_points;
+};
+
+inline bool
+supported_pointer_equiv_p (tree expr)
+{
+  return TREE_CODE (expr) == SSA_NAME && POINTER_TYPE_P (TREE_TYPE (expr));
+}
+
+#endif // GCC_VALUE_POINTER_EQUIV_H