A64: Debug code should assert on unexpected situation.

src/a64/lithium-codegen-a64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3647 matching lines @@
   __ Bind(&runtime_allocation);
   if (FLAG_debug_code) {
     // Because result is in the pointer map, we need to make sure it has a valid
     // tagged value before we call the runtime. We speculatively set it to the
     // input (for abs(+x)) or to a smi (for abs(-SMI_MIN)), so it should already
     // be valid.
     Label result_ok;
     Register input = ToRegister(instr->value());
     __ JumpIfSmi(result, &result_ok);
     __ Cmp(input, result);
-    // TODO(all): Shouldn't we assert here?
-    DeoptimizeIf(ne, instr->environment());
+    __ Assert(eq, kUnexpectedValue);
     __ Bind(&result_ok);
   }
 
   { PushSafepointRegistersScope scope(this, Safepoint::kWithRegisters);
     CallRuntimeFromDeferred(Runtime::kAllocateHeapNumber, 0, instr,
                             instr->context());
     __ StoreToSafepointRegisterSlot(x0, result);
   }
   // The inline (non-deferred) code will store result_bits into result.
 }
@@ skipping 1986 matching lines @@
   __ Bind(&out_of_object);
   __ Ldr(result, FieldMemOperand(object, JSObject::kPropertiesOffset));
   // Index is equal to negated out of object property index plus 1.
   __ Sub(result, result, Operand::UntagSmiAndScale(index, kPointerSizeLog2));
   __ Ldr(result, FieldMemOperand(result,
                                  FixedArray::kHeaderSize - kPointerSize));
   __ Bind(&done);
 }
 
 } }  // namespace v8::internal