Add checks to runtime functions.

src/x64/lithium-codegen-x64.cc

Index: src/x64/lithium-codegen-x64.cc
diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index fea7627002095527cc2b0ec1c4e32cc456b30f33..89e311e4614b10cfe000b417a61c3bf7515b9c85 100644
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -1332,15 +1332,14 @@ void LCodeGen::DoDateField(LDateField* instr) {
   Register object = ToRegister(instr->InputAt(0));
   Register result = ToRegister(instr->result());
   Smi* index = instr->index();
-  Label runtime, done;
+  Label runtime, done, not_date_object;
   ASSERT(object.is(result));
   ASSERT(object.is(rax));
 
-#ifdef DEBUG
-  __ AbortIfSmi(object);
+  Condition cc = masm()->CheckSmi(object);
+  DeoptimizeIf(cc, instr->environment());
   __ CmpObjectType(object, JS_DATE_TYPE, kScratchRegister);
-  __ Assert(equal, "Trying to get date field from non-date.");
-#endif
+  DeoptimizeIf(not_equal, instr->environment());
 
   if (index->value() == 0) {
     __ movq(result, FieldOperand(object, JSDate::kValueOffset));
@@ -1959,9 +1958,7 @@ void LCodeGen::DoGetCachedArrayIndex(LGetCachedArrayIndex* instr) {
   Register input = ToRegister(instr->InputAt(0));
   Register result = ToRegister(instr->result());
 
-  if (FLAG_debug_code) {
-    __ AbortIfNotString(input);
-  }
+  __ AbortIfNotString(input);
 
   __ movl(result, FieldOperand(input, String::kHashFieldOffset));
   ASSERT(String::kHashShift >= kSmiTagSize);