Implement optimized unary ops for ia32 as well. Fix a crash in disassembler.

runtime/vm/disassembler_ia32.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/disassembler.h"
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_IA32.
 #if defined(TARGET_ARCH_IA32)
 #include "platform/utils.h"
 #include "vm/allocation.h"
@@ skipping 412 matching lines @@
     const char* name_of_stub = StubCode::NameOfStub(addr);
     if (name_of_stub != NULL) {
       Print("  [stub: ");
       Print(name_of_stub);
       Print("]");
     } else {
       // Print only if jumping to entry point.
       const Code& code = Code::Handle(Code::LookupCode(addr));
       if (!code.IsNull() && (code.EntryPoint() == addr)) {
         const Function& function = Function::Handle(code.function());
-        const char* name_of_function = function.ToFullyQualifiedCString();
-        Print(" [");
-        Print(name_of_function);
-        Print("]");
+        if (function.IsNull()) {
+          Print(" [ stub ]");
+        } else {
+          const char* name_of_function = function.ToFullyQualifiedCString();
+          Print(" [");
+          Print(name_of_function);
+          Print("]");
+        }
       }
     }
   }
 }
 
 
 int X86Decoder::PrintRightOperandHelper(uint8_t* modrmp,
                                         RegisterNamePrinter register_printer) {
   int mod, regop, rm;
   GetModRm(*modrmp, &mod, &regop, &rm);
@@ skipping 1147 matching lines @@
                                   human_buffer,
                                   sizeof(human_buffer),
                                   pc);
     pc += instruction_length;
   }
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32