expr.c (build_java_array_length_access): Check for null pointer.

2002-09-26  Andrew Haley  <aph@redhat.com>

	* expr.c (build_java_array_length_access): Check for null pointer.
	* expr.c (expand_java_arrayload): Likewise.

From-SVN: r57591

2 files changed, 29 insertions, 6 deletions

diff --git a/gcc/java/ChangeLog b/gcc/java/ChangeLog
index 45776e6..620543a 100644
--- a/gcc/java/ChangeLog
+++ b/gcc/java/ChangeLog
@@ -1,3 +1,8 @@
+2002-09-26  Andrew Haley  <aph@redhat.com>
+
+	* expr.c (build_java_array_length_access): Check for null pointer.
+	* expr.c (expand_java_arrayload): Likewise.
+
 2002-09-21  Richard Henderson  <rth@redhat.com>
 
 	* jcf-parse.c (get_constant): Decode from IEEE no matter 
diff --git a/gcc/java/expr.c b/gcc/java/expr.c
index c192d46..0c434e9 100644
--- a/gcc/java/expr.c
+++ b/gcc/java/expr.c
@@ -675,6 +675,15 @@ build_java_array_length_access (node)
   tree array_type = TREE_TYPE (type);
   HOST_WIDE_INT length;
 
+  /* JVM spec: If the arrayref is null, the arraylength instruction
+     throws a NullPointerException.  The only way we could get a node
+     of type ptr_type_node at this point is `aconst_null; arraylength'
+     or something equivalent.  */
+  if (type == ptr_type_node)
+    return build (CALL_EXPR, int_type_node, 
+		  build_address_of (soft_nullpointer_node),
+		  NULL_TREE, NULL_TREE);
+
   if (!is_array_type_p (type))
     abort ();
 
@@ -1028,12 +1037,21 @@ expand_java_arrayload (lhs_type_node )
 
   index_node = save_expr (index_node);
   array_node = save_expr (array_node);
-  lhs_type_node   = build_java_check_indexed_type (array_node, lhs_type_node);
-
-  load_node = build_java_arrayaccess (array_node,
-				      lhs_type_node,
-				      index_node);
-
+  
+  if (TREE_TYPE (array_node) == ptr_type_node)
+    /* The only way we could get a node of type ptr_type_node at this
+       point is `aconst_null; arraylength' or something equivalent, so
+       unconditionally throw NullPointerException.  */    
+    load_node = build (CALL_EXPR, lhs_type_node, 
+		       build_address_of (soft_nullpointer_node),
+		       NULL_TREE, NULL_TREE);
+  else
+    {
+      lhs_type_node = build_java_check_indexed_type (array_node, lhs_type_node);
+      load_node = build_java_arrayaccess (array_node,
+					  lhs_type_node,
+					  index_node);
+    }
   if (INTEGRAL_TYPE_P (lhs_type_node) && TYPE_PRECISION (lhs_type_node) <= 32)
     load_node = fold (build1 (NOP_EXPR, int_type_node, load_node));
   push_value (load_node);