Remove the unused HElementsKind instruction.

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index bcb351c6385d06d2ca7b4e6efc64ca0d1bbdbebe..b5f31eeec2bfe503558066960df6c59483bdcc06 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -1968,21 +1968,6 @@ void LCodeGen::DoMapEnumLength(LMapEnumLength* instr) {
 }
 
 
-void LCodeGen::DoElementsKind(LElementsKind* instr) {
-  Register result = ToRegister(instr->result());
-  Register input = ToRegister(instr->value());
-
-  // Load map into |result|.
-  __ mov(result, FieldOperand(input, HeapObject::kMapOffset));
-  // Load the map's "bit field 2" into |result|. We only need the first byte,
-  // but the following masking takes care of that anyway.
-  __ mov(result, FieldOperand(result, Map::kBitField2Offset));
-  // Retrieve elements_kind from bit field 2.
-  __ and_(result, Map::kElementsKindMask);
-  __ shr(result, Map::kElementsKindShift);
-}
-
-
 void LCodeGen::DoValueOf(LValueOf* instr) {
   Register input = ToRegister(instr->value());
   Register result = ToRegister(instr->result());