New class for Date objects: caches individual date components.

src/arm/lithium-arm.cc

Index: src/arm/lithium-arm.cc
diff --git a/src/arm/lithium-arm.cc b/src/arm/lithium-arm.cc
index 7e6dff3edf78b61d441a510cbbf6fee69e6121f9..30e4a5a3ad437b8cc1e1814da27a5c4dd913ba19 100644
--- a/src/arm/lithium-arm.cc
+++ b/src/arm/lithium-arm.cc
@@ -1589,6 +1589,22 @@ LInstruction* LChunkBuilder::DoValueOf(HValueOf* instr) {
 }
 
 
+LInstruction* LChunkBuilder::DoDateField(HDateField* instr) {
+  LOperand* object = UseRegister(instr->value());
+  LDateField* result = new LDateField(object, TempRegister(), instr->index());
+  return DefineAsRegister(result);
+}
+
+
+LInstruction* LChunkBuilder::DoSetDateField(HSetDateField* instr) {
+  LOperand* date = UseRegister(instr->OperandAt(1));
+  LOperand* value = UseRegister(instr->OperandAt(2));
+  LSetDateField* result =
+      new LSetDateField(date, value, TempRegister(), instr->index());
+  return DefineAsRegister(result);
+}
+
+
 LInstruction* LChunkBuilder::DoBoundsCheck(HBoundsCheck* instr) {
   return AssignEnvironment(new LBoundsCheck(UseRegisterAtStart(instr->index()),
                                             UseRegister(instr->length())));