Cleanup include guards:

src/ia32/simulator-ia32.h

 // Copyright 2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
 //       with the distribution.
 //     * Neither the name of Google Inc. nor the names of its
 //       contributors may be used to endorse or promote products derived
 //       from this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-#ifndef V8_SIMULATOR_IA32_H_
-#define V8_SIMULATOR_IA32_H_
+#ifndef V8_IA32_SIMULATOR_IA32_H_
+#define V8_IA32_SIMULATOR_IA32_H_
 
 
 // Since there is no simulator for the ia32 architecture the only thing we can
 // do is to call the entry directly.
 #define CALL_GENERATED_CODE(entry, p0, p1, p2, p3, p4) \
   entry(p0, p1, p2, p3, p4);
 
 // Calculated the stack limit beyond which we will throw stack overflow errors.
 // This macro must be called from a C++ method. It relies on being able to take
 // the address of "this" to get a value on the current execution stack and then
 // calculates the stack limit based on that value.
 // NOTE: The check for overflow is not safe as there is no guarantee that the
 // running thread has its stack in all memory up to address 0x00000000.
 #define GENERATED_CODE_STACK_LIMIT(limit) \
   (reinterpret_cast<uintptr_t>(this) >= limit ? \
       reinterpret_cast<uintptr_t>(this) - limit : 0)
 
-#endif  // V8_SIMULATOR_IA32_H_
+#endif  // V8_IA32_SIMULATOR_IA32_H_