[MIPS] Forbid $sp update at the end of the last bundle.

src/trusted/validator_mips/model.h

Index: src/trusted/validator_mips/model.h
diff --git a/src/trusted/validator_mips/model.h b/src/trusted/validator_mips/model.h
index 2d0ab249b37d32155e2ea7b638d6fff31e98f324..fc709cb936b523b59bd080a9e8d0a1f7a64afd5d 100644
--- a/src/trusted/validator_mips/model.h
+++ b/src/trusted/validator_mips/model.h
@@ -1,8 +1,7 @@
 /*
- * Copyright 2012 The Native Client Authors.  All rights reserved.
- * Use of this source code is governed by a BSD-style license that can
- * be found in the LICENSE file.
- * Copyright 2012, Google Inc.
+ * Copyright (c) 2012 The Native Client Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
  */
 
 #ifndef NATIVE_CLIENT_SRC_TRUSTED_VALIDATOR_MIPS_MODEL_H
@@ -78,7 +77,7 @@ class RegisterList {
    *  - It inlines to a single machine instruction,
    *  - The readability gain in inst_classes.cc is large.
    */
-  inline RegisterList(const Register r);
+  explicit inline RegisterList(const Register r);
 
   /*
    * Checks whether this list contains the given register.
@@ -153,6 +152,9 @@ uint32_t const kInstrSize   = 4;
 uint32_t const kInstrAlign  = 0xFFFFFFFC;
 uint32_t const kBundleAlign = 0xFFFFFFF0;
 
+// Opcode for nop instruction.
+uint32_t const kNop = 0x0;
+
 }  // namespace
 
 // Definitions for our inlined functions.