Make ssa_cache a range_query.

By providing range_of_expr as a range_query, we can fold and do other
interesting things using values from the global table.  Make ranger's
knonw globals available via const_query.

	* gimple-range-cache.cc (ssa_cache::range_of_expr): New.
	* gimple-range-cache.h (class ssa_cache): Inherit from range_query.
	(ranger_cache::const_query): New.
	* gimple-range.cc (gimple_ranger::const_query): New.
	* gimple-range.h (gimple_ranger::const_query): New prototype.

4 files changed, 27 insertions, 1 deletions

diff --git a/gcc/gimple-range-cache.cc b/gcc/gimple-range-cache.cc
index f25abaf..52165d2 100644
--- a/gcc/gimple-range-cache.cc
+++ b/gcc/gimple-range-cache.cc
@@ -545,6 +545,20 @@ ssa_cache::~ssa_cache ()
   delete m_range_allocator;
 }
 
+// Enable a query to evaluate staements/ramnges based on picking up ranges
+// from just an ssa-cache.
+
+bool
+ssa_cache::range_of_expr (vrange &r, tree expr, gimple *stmt)
+{
+  if (!gimple_range_ssa_p (expr))
+    return get_tree_range (r, expr, stmt);
+
+  if (!get_range (r, expr))
+    gimple_range_global (r, expr, cfun);
+  return true;
+}
+
 // Return TRUE if the global range of NAME has a cache entry.
 
 bool
diff --git a/gcc/gimple-range-cache.h b/gcc/gimple-range-cache.h
index 4fc9823..afcf8d7 100644
--- a/gcc/gimple-range-cache.h
+++ b/gcc/gimple-range-cache.h
@@ -52,7 +52,7 @@ private:
 // has been visited during this incarnation.  Once the ranger evaluates
 // a name, it is typically not re-evaluated again.
 
-class ssa_cache
+class ssa_cache : public range_query
 {
 public:
   ssa_cache ();
@@ -63,6 +63,8 @@ public:
   virtual void clear_range (tree name);
   virtual void clear ();
   void dump (FILE *f = stderr);
+  virtual bool range_of_expr (vrange &r, tree expr, gimple *stmt);
+
 protected:
   vec<vrange_storage *> m_tab;
   vrange_allocator *m_range_allocator;
@@ -103,6 +105,7 @@ public:
   bool get_global_range (vrange &r, tree name) const;
   bool get_global_range (vrange &r, tree name, bool &current_p);
   void set_global_range (tree name, const vrange &r, bool changed = true);
+  range_query &const_query () { return m_globals; }
 
   void propagate_updated_value (tree name, basic_block bb);
 
diff --git a/gcc/gimple-range.cc b/gcc/gimple-range.cc
index 4fae3f9..01e62d3 100644
--- a/gcc/gimple-range.cc
+++ b/gcc/gimple-range.cc
@@ -70,6 +70,14 @@ gimple_ranger::~gimple_ranger ()
   m_stmt_list.release ();
 }
 
+// Return a range_query which accesses just the known global values.
+
+range_query &
+gimple_ranger::const_query ()
+{
+  return m_cache.const_query ();
+}
+
 bool
 gimple_ranger::range_of_expr (vrange &r, tree expr, gimple *stmt)
 {
diff --git a/gcc/gimple-range.h b/gcc/gimple-range.h
index e3aa947..6587e49 100644
--- a/gcc/gimple-range.h
+++ b/gcc/gimple-range.h
@@ -64,6 +64,7 @@ public:
   bool fold_stmt (gimple_stmt_iterator *gsi, tree (*) (tree));
   void register_inferred_ranges (gimple *s);
   void register_transitive_inferred_ranges (basic_block bb);
+  range_query &const_query ();
 protected:
   bool fold_range_internal (vrange &r, gimple *s, tree name);
   void prefill_name (vrange &r, tree name);