Add an IC for CompareNil operations

src/ia32/lithium-ia32.cc

Index: src/ia32/lithium-ia32.cc
diff --git a/src/ia32/lithium-ia32.cc b/src/ia32/lithium-ia32.cc
index 523673ae2febbe0699d6992d16c9440cdb3fa6ba..cbb554f0e34a764165b150f0a1f360a0bb40712d 100644
--- a/src/ia32/lithium-ia32.cc
+++ b/src/ia32/lithium-ia32.cc
@@ -230,15 +230,6 @@ void LCmpIDAndBranch::PrintDataTo(StringStream* stream) {
 }
 
 
-void LIsNilAndBranch::PrintDataTo(StringStream* stream) {
-  stream->Add("if ");
-  value()->PrintTo(stream);
-  stream->Add(kind() == kStrictEquality ? " === " : " == ");
-  stream->Add(nil() == kNullValue ? "null" : "undefined");
-  stream->Add(" then B%d else B%d", true_block_id(), false_block_id());
-}
-
-
 void LIsObjectAndBranch::PrintDataTo(StringStream* stream) {
   stream->Add("if is_object(");
   value()->PrintTo(stream);
@@ -1711,13 +1702,6 @@ LInstruction* LChunkBuilder::DoCompareConstantEqAndBranch(
 }
 
 
-LInstruction* LChunkBuilder::DoIsNilAndBranch(HIsNilAndBranch* instr) {
-  // We only need a temp register for non-strict compare.
-  LOperand* temp = instr->kind() == kStrictEquality ? NULL : TempRegister();
-  return new(zone()) LIsNilAndBranch(UseRegisterAtStart(instr->value()), temp);
-}
-
-
 LInstruction* LChunkBuilder::DoIsObjectAndBranch(HIsObjectAndBranch* instr) {
   ASSERT(instr->value()->representation().IsTagged());
   LOperand* temp = TempRegister();