[PATCH v3 03/11] [PR gdb/14441] gdb: valops: add ability to return rvalue reference values from value_ref()

[Artemiy Volkov <artemiyv at acm dot org>]

Parameterize value_ref() by the kind of reference type the value of which
is requested. Change all callers to use the new API.

gdb/ChangeLog:

2016-03-04  Artemiy Volkov  <artemiyv@acm.org>

    * ada-lang.c (ada_evaluate_subexp): Adhere to the new
    value_ref() interface.
    * c-valprint.c (c_value_print): Likewise.
    * infcall.c (value_arg_coerce): Likewise.
    * python/py-value.c (valpy_reference_value): Likewise.
    * valops.c (value_cast, value_reinterpret_cast)
    (value_dynamic_cast, typecmp): Likewise.
    (value_ref): Parameterize by kind of return value reference type.
    * value.h (value_ref): Add new parameter "refcode".
---
 gdb/ada-lang.c        |  2 +-
 gdb/c-valprint.c      |  9 ++++++---
 gdb/infcall.c         |  2 +-
 gdb/python/py-value.c |  2 +-
 gdb/valops.c          | 25 +++++++++++++++++--------
 gdb/value.h           |  2 +-
 6 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index d874129..585d729 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -10724,7 +10724,7 @@ ada_evaluate_subexp (struct type *expect_type, struct expression *exp,
 		     should return a ref as it should be valid to ask
 		     for its address; so rebuild a ref after coerce.  */
 		  arg1 = ada_coerce_ref (arg1);
-		  return value_ref (arg1);
+		  return value_ref (arg1, TYPE_CODE_REF);
 		}
 	    }
 
diff --git a/gdb/c-valprint.c b/gdb/c-valprint.c
index 62552ec..a1f5db6 100644
--- a/gdb/c-valprint.c
+++ b/gdb/c-valprint.c
@@ -602,10 +602,13 @@ c_value_print (struct value *val, struct ui_file *stream,
       else if (options->objectprint
 	       && (TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_STRUCT))
 	{
-	  int is_ref = TYPE_CODE (type) == TYPE_CODE_REF;
+	  int is_ref = TYPE_IS_REFERENCE (type);
+	  enum type_code refcode = TYPE_CODE_UNDEF;
 
-	  if (is_ref)
+	  if (is_ref) {
 	    val = value_addr (val);
+	    refcode = TYPE_CODE (type);
+	  }
 
 	  /* Pointer to class, check real type of object.  */
 	  fprintf_filtered (stream, "(");
@@ -625,7 +628,7 @@ c_value_print (struct value *val, struct ui_file *stream,
 
 		  if (is_ref)
 		    {
-		      val = value_ref (value_ind (val));
+		      val = value_ref (value_ind (val), refcode);
 		      type = value_type (val);
 		    }
 
diff --git a/gdb/infcall.c b/gdb/infcall.c
index 77cd931..ad2512a 100644
--- a/gdb/infcall.c
+++ b/gdb/infcall.c
@@ -169,7 +169,7 @@ value_arg_coerce (struct gdbarch *gdbarch, struct value *arg,
 	   if the value was not previously in memory - in some cases
 	   we should clearly be allowing this, but how?  */
 	new_value = value_cast (TYPE_TARGET_TYPE (type), arg);
-	new_value = value_ref (new_value);
+	new_value = value_ref (new_value, TYPE_CODE (type));
 	return new_value;
       }
     case TYPE_CODE_INT:
diff --git a/gdb/python/py-value.c b/gdb/python/py-value.c
index be08231..141f180 100644
--- a/gdb/python/py-value.c
+++ b/gdb/python/py-value.c
@@ -249,7 +249,7 @@ valpy_reference_value (PyObject *self, PyObject *args)
       struct cleanup *cleanup = make_cleanup_value_free_to_mark (value_mark ());
 
       self_val = ((value_object *) self)->value;
-      result = value_to_value_object (value_ref (self_val));
+      result = value_to_value_object (value_ref (self_val, TYPE_CODE_REF));
 
       do_cleanups (cleanup);
     }
diff --git a/gdb/valops.c b/gdb/valops.c
index 1aafb5a..1f423a0 100644
--- a/gdb/valops.c
+++ b/gdb/valops.c
@@ -372,7 +372,7 @@ value_cast (struct type *type, struct value *arg2)
       struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
       struct value *val =  value_cast (dereftype, arg2);
 
-      return value_ref (val); 
+      return value_ref (val, TYPE_CODE (t1));
     }
 
   code2 = TYPE_CODE (check_typedef (value_type (arg2)));
@@ -622,7 +622,8 @@ value_reinterpret_cast (struct type *type, struct value *arg)
     error (_("Invalid reinterpret_cast"));
 
   if (is_ref)
-    result = value_cast (type, value_ref (value_ind (result)));
+    result = value_cast (type, value_ref (value_ind (result),
+                                          TYPE_CODE (type)));
 
   return result;
 }
@@ -816,7 +817,9 @@ value_dynamic_cast (struct type *type, struct value *arg)
 				arg_type,
 				&result) == 1)
 	return value_cast (type,
-			   is_ref ? value_ref (result) : value_addr (result));
+			   is_ref
+			   ? value_ref (result, TYPE_CODE (resolved_type))
+			   : value_addr (result));
     }
 
   /* The second dynamic check specified in 5.2.7.  */
@@ -828,7 +831,9 @@ value_dynamic_cast (struct type *type, struct value *arg)
 			       value_address (tem), tem,
 			       rtti_type, &result) == 1)
     return value_cast (type,
-		       is_ref ? value_ref (result) : value_addr (result));
+		       is_ref
+		       ? value_ref (result, TYPE_CODE (resolved_type))
+		       : value_addr (result));
 
   if (TYPE_CODE (resolved_type) == TYPE_CODE_PTR)
     return value_zero (type, not_lval);
@@ -1499,16 +1504,20 @@ value_addr (struct value *arg1)
    contents.  */
 
 struct value *
-value_ref (struct value *arg1)
+value_ref (struct value *arg1, enum type_code refcode)
 {
   struct value *arg2;
   struct type *type = check_typedef (value_type (arg1));
 
-  if (TYPE_CODE (type) == TYPE_CODE_REF)
+  gdb_assert (refcode == TYPE_CODE_REF || refcode == TYPE_CODE_RVALUE_REF);
+
+  if ((TYPE_CODE (type) == TYPE_CODE_REF
+       || TYPE_CODE (type) == TYPE_CODE_RVALUE_REF)
+      && TYPE_CODE (type) == refcode)
     return arg1;
 
   arg2 = value_addr (arg1);
-  deprecated_set_value_type (arg2, lookup_lvalue_reference_type (type));
+  deprecated_set_value_type (arg2, lookup_reference_type (type, refcode));
   return arg2;
 }
 
@@ -1715,7 +1724,7 @@ typecmp (int staticp, int varargs, int nargs,
 	  if (TYPE_CODE (tt2) == TYPE_CODE_ARRAY)
 	    t2[i] = value_coerce_array (t2[i]);
 	  else
-	    t2[i] = value_ref (t2[i]);
+	    t2[i] = value_ref (t2[i], TYPE_CODE (tt1));
 	  continue;
 	}
 
diff --git a/gdb/value.h b/gdb/value.h
index 2eac5ef..db1b7bf 100644
--- a/gdb/value.h
+++ b/gdb/value.h
@@ -725,7 +725,7 @@ extern struct value *value_ind (struct value *arg1);
 
 extern struct value *value_addr (struct value *arg1);
 
-extern struct value *value_ref (struct value *arg1);
+extern struct value *value_ref (struct value *arg1, enum type_code refcode);
 
 extern struct value *value_assign (struct value *toval,
 				   struct value *fromval);
-- 
2.7.2