Support get_or_insert in ordered_hash_map

Get_or_insert method is already supported by the unordered hash map.
Adding it to the ordered map enables us to replace the unordered map
with the ordered one in cases where ordering may be useful.

Signed-off-by: Andrzej Turko <andrzej.turko@gmail.com>

gcc/ChangeLog:

	* ordered-hash-map.h: Add get_or_insert.
	* ordered-hash-map-tests.cc: Use get_or_insert in tests.

2 files changed, 41 insertions, 4 deletions

diff --git a/gcc/ordered-hash-map-tests.cc b/gcc/ordered-hash-map-tests.cc
index 1c26bbf..55894c2 100644
--- a/gcc/ordered-hash-map-tests.cc
+++ b/gcc/ordered-hash-map-tests.cc
@@ -58,6 +58,7 @@ static void
 test_map_of_strings_to_int ()
 {
   ordered_hash_map <const char *, int> m;
+  bool existed;
 
   const char *ostrich = "ostrich";
   const char *elephant = "elephant";
@@ -74,17 +75,23 @@ test_map_of_strings_to_int ()
   ASSERT_EQ (false, m.put (ostrich, 2));
   ASSERT_EQ (false, m.put (elephant, 4));
   ASSERT_EQ (false, m.put (ant, 6));
-  ASSERT_EQ (false, m.put (spider, 8));
+  existed = true;
+  int &value = m.get_or_insert (spider, &existed);
+  value = 8;
+  ASSERT_EQ (false, existed);
   ASSERT_EQ (false, m.put (millipede, 750));
   ASSERT_EQ (false, m.put (eric, 3));
 
+
   /* Verify that we can recover the stored values.  */
   ASSERT_EQ (6, m.elements ());
   ASSERT_EQ (2, *m.get (ostrich));
   ASSERT_EQ (4, *m.get (elephant));
   ASSERT_EQ (6, *m.get (ant));
   ASSERT_EQ (8, *m.get (spider));
-  ASSERT_EQ (750, *m.get (millipede));
+  existed = false;
+  ASSERT_EQ (750, m.get_or_insert (millipede, &existed));
+  ASSERT_EQ (true, existed);
   ASSERT_EQ (3, *m.get (eric));
 
   /* Verify that the order of insertion is preserved.  */
@@ -113,6 +120,7 @@ test_map_of_int_to_strings ()
 {
   const int EMPTY = -1;
   const int DELETED = -2;
+  bool existed;
   typedef int_hash <int, EMPTY, DELETED> int_hash_t;
   ordered_hash_map <int_hash_t, const char *> m;
 
@@ -131,7 +139,9 @@ test_map_of_int_to_strings ()
   ASSERT_EQ (false, m.put (2, ostrich));
   ASSERT_EQ (false, m.put (4, elephant));
   ASSERT_EQ (false, m.put (6, ant));
-  ASSERT_EQ (false, m.put (8, spider));
+  const char* &value = m.get_or_insert (8, &existed);
+  value = spider;
+  ASSERT_EQ (false, existed);
   ASSERT_EQ (false, m.put (750, millipede));
   ASSERT_EQ (false, m.put (3, eric));
 
@@ -141,7 +151,8 @@ test_map_of_int_to_strings ()
   ASSERT_EQ (*m.get (4), elephant);
   ASSERT_EQ (*m.get (6), ant);
   ASSERT_EQ (*m.get (8), spider);
-  ASSERT_EQ (*m.get (750), millipede);
+  ASSERT_EQ (m.get_or_insert (750, &existed), millipede);
+  ASSERT_EQ (existed, TRUE);
   ASSERT_EQ (*m.get (3), eric);
 
   /* Verify that the order of insertion is preserved.  */
diff --git a/gcc/ordered-hash-map.h b/gcc/ordered-hash-map.h
index 6b68cc9..9fc8751 100644
--- a/gcc/ordered-hash-map.h
+++ b/gcc/ordered-hash-map.h
@@ -76,6 +76,32 @@ public:
     return m_map.get (k);
   }
 
+  /* Return a reference to the value for the passed in key, creating the entry
+    if it doesn't already exist.  If existed is not NULL then it is set to
+    false if the key was not previously in the map, and true otherwise.  */
+
+  Value &get_or_insert (const Key &k, bool *existed = NULL)
+  {
+    bool _existed;
+    Value &ret = m_map.get_or_insert (k, &_existed);
+
+    if (!_existed)
+      {
+	bool key_present;
+	int &slot = m_key_index.get_or_insert (k, &key_present);
+	if (!key_present)
+	  {
+	    slot = m_keys.length ();
+	    m_keys.safe_push (k);
+	  }
+      }
+
+    if (existed)
+      *existed = _existed;
+
+    return ret;
+  }
+
   /* Removing a key removes it from the map, but retains the insertion
      order.  */