7140882: Don't return booleans from methods returning pointers

Changed "return false" to "return NULL"

Reviewed-by: dholmes, rottenha
diff --git a/hotspot/src/share/vm/oops/constantPoolOop.cpp b/hotspot/src/share/vm/oops/constantPoolOop.cpp
index 87280c6..493249d 100644
--- a/hotspot/src/share/vm/oops/constantPoolOop.cpp
+++ b/hotspot/src/share/vm/oops/constantPoolOop.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -269,7 +269,7 @@
 methodOop constantPoolOopDesc::method_at_if_loaded(constantPoolHandle cpool,
                                                    int which, Bytecodes::Code invoke_code) {
   assert(!constantPoolCacheOopDesc::is_secondary_index(which), "no indy instruction here");
-  if (cpool->cache() == NULL)  return false;  // nothing to load yet
+  if (cpool->cache() == NULL)  return NULL;  // nothing to load yet
   int cache_index = which - CPCACHE_INDEX_TAG;
   if (!(cache_index >= 0 && cache_index < cpool->cache()->length())) {
     if (PrintMiscellaneous && (Verbose||WizardMode)) {
diff --git a/hotspot/src/share/vm/opto/loopnode.cpp b/hotspot/src/share/vm/opto/loopnode.cpp
index 6c7b8ed..2d045e4 100644
--- a/hotspot/src/share/vm/opto/loopnode.cpp
+++ b/hotspot/src/share/vm/opto/loopnode.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2012, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -898,7 +898,7 @@
 Node* CountedLoopNode::match_incr_with_optional_truncation(
                       Node* expr, Node** trunc1, Node** trunc2, const TypeInt** trunc_type) {
   // Quick cutouts:
-  if (expr == NULL || expr->req() != 3)  return false;
+  if (expr == NULL || expr->req() != 3)  return NULL;
 
   Node *t1 = NULL;
   Node *t2 = NULL;