Add checks to runtime functions.

src/arm/lithium-codegen-arm.cc

Index: src/arm/lithium-codegen-arm.cc
diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index 9f4a789724082adf0d3e7f9c34b671ddbe80109f..8d5c7faef153ae34d3c0fa9616b24955db797ed6 100644
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -1592,11 +1592,10 @@ void LCodeGen::DoDateField(LDateField* instr) {
   ASSERT(!scratch.is(scratch0()));
   ASSERT(!scratch.is(object));
 
-#ifdef DEBUG
-  __ AbortIfSmi(object);
+  __ tst(object, Operand(kSmiTagMask));
+  DeoptimizeIf(eq, instr->environment());
   __ CompareObjectType(object, scratch, scratch, JS_DATE_TYPE);
-  __ Assert(eq, "Trying to get date field from non-date.");
-#endif
+  DeoptimizeIf(ne, instr->environment());
 
   if (index->value() == 0) {
     __ ldr(result, FieldMemOperand(object, JSDate::kValueOffset));
@@ -2232,9 +2231,7 @@ void LCodeGen::DoGetCachedArrayIndex(LGetCachedArrayIndex* instr) {
   Register input = ToRegister(instr->InputAt(0));
   Register result = ToRegister(instr->result());
 
-  if (FLAG_debug_code) {
-    __ AbortIfNotString(input);
-  }
+  __ AbortIfNotString(input);
 
   __ ldr(result, FieldMemOperand(input, String::kHashFieldOffset));
   __ IndexFromHash(result, result);