[optimizing] trivial x86 explicit null check fix

Change a cmp reg,0 to test reg,reg.  I don't know that this code
is even invoked.

Change-Id: Ifddffcb22d8a4060b7abbea17d8e7168535e409b
Signed-off-by: Mark Mendell <mark.p.mendell@intel.com>

diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index 8d0ca0b..0d5fe49 100644 (file)
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -3146,7 +3146,7 @@ void InstructionCodeGeneratorX86::GenerateExplicitNullCheck(HNullCheck* instruct
   Location obj = locations->InAt(0);
 
   if (obj.IsRegister()) {
-    __ cmpl(obj.AsRegister<Register>(), Immediate(0));
+    __ testl(obj.AsRegister<Register>(), obj.AsRegister<Register>());
   } else if (obj.IsStackSlot()) {
     __ cmpl(Address(ESP, obj.GetStackIndex()), Immediate(0));
   } else {