Add support for enabling DCHECKs in release mode

src/x64/deoptimizer-x64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/codegen.h"
 #include "src/deoptimizer.h"
@@ skipping 37 matching lines @@
     }
   }
 
   // For each LLazyBailout instruction insert a absolute call to the
   // corresponding deoptimization entry, or a short call to an absolute
   // jump if space is short. The absolute jumps are put in a table just
   // before the safepoint table (space was allocated there when the Code
   // object was created, if necessary).
 
   Address instruction_start = code->instruction_start();
-#ifdef DEBUG
+#if DCHECK_IS_ON
   Address prev_call_address = NULL;
 #endif
   DeoptimizationInputData* deopt_data =
       DeoptimizationInputData::cast(code->deoptimization_data());
   deopt_data->SetSharedFunctionInfo(Smi::FromInt(0));
   // For each LLazyBailout instruction insert a call to the corresponding
   // deoptimization entry.
   for (int i = 0; i < deopt_data->DeoptCount(); i++) {
     if (deopt_data->Pc(i)->value() == -1) continue;
     // Position where Call will be patched in.
     Address call_address = instruction_start + deopt_data->Pc(i)->value();
     // There is room enough to write a long call instruction because we pad
     // LLazyBailout instructions with nops if necessary.
     CodePatcher patcher(call_address, Assembler::kCallSequenceLength);
     patcher.masm()->Call(GetDeoptimizationEntry(isolate, i, LAZY),
                          Assembler::RelocInfoNone());
     DCHECK(prev_call_address == NULL ||
            call_address >= prev_call_address + patch_size());
     DCHECK(call_address + patch_size() <= code->instruction_end());
-#ifdef DEBUG
+#if DCHECK_IS_ON
     prev_call_address = call_address;
 #endif
   }
 }
 
 
 void Deoptimizer::FillInputFrame(Address tos, JavaScriptFrame* frame) {
   // Set the register values. The values are not important as there are no
   // callee saved registers in JavaScript frames, so all registers are
   // spilled. Registers rbp and rsp are set to the correct values though.
@@ skipping 254 matching lines @@
   UNREACHABLE();
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64